What does correlation have to do with causation?

2015-11-182015-11-14 PNRJ core principles, statistics causation, correlation, corruption, experiment, Granger causality, halo effect, Higgs, inequality, logic, natural experiment, quasi-experiment, science, statistics

JDN 2457345

I’ve been thinking of expanding the topics of this blog into some basic statistics and econometrics. It has been said that there are “Lies, damn lies, and statistics”; but in fact it’s almost the opposite—there are truths, whole truths, and statistics. Almost everything in the world that we know—not merely guess, or suppose, or intuit, or believe, but actually know, with a quantifiable level of certainty—is done by means of statistics. All sciences are based on them, from physics (when they say the Higgs discovery is a “5-sigma event”, that’s a statistic) to psychology, ecology to economics. Far from being something we cannot trust, they are in a sense the only thing we can trust.

The reason it sometimes feels like we cannot trust statistics is that most people do not understand statistics very well; this creates opportunities for both accidental confusion and willful distortion. My hope is therefore to provide you with some of the basic statistical knowledge you need to combat the worst distortions and correct the worst confusions.

I wasn’t quite sure where to start on this quest, but I suppose I have to start somewhere. I figured I may as well start with an adage about statistics that I hear commonly abused: “Correlation does not imply causation.”

Taken at its original meaning, this is definitely true. Unfortunately, it can be easily abused or misunderstood.

In its original meaning, the formal sense of the word “imply” meaning logical implication, to “imply” something is an extremely strong statement. It means that you logically entail that result, that if the antecedent is true, the consequent must be true, on pain of logical contradiction. Logical implication is for most practical purposes synonymous with mathematical proof. (Unfortunately, it’s not quite synonymous, because of things like Gödel’s incompleteness theorems and Löb’s theorem.)

And indeed, correlation does not logically entail causation; it’s quite possible to have correlations without any causal connection whatsoever, simply by chance. One of my former professors liked to brag that from 1990 to 2010 whether or not she ate breakfast had a statistically significant positive correlation with that day’s closing price for the Dow Jones Industrial Average.

How is this possible? Did my professor actually somehow influence the stock market by eating breakfast? Of course not; if she could do that, she’d be a billionaire by now. And obviously the Dow’s price at 17:00 couldn’t influence whether she ate breakfast at 09:00. Could there be some common cause driving both of them, like the weather? I guess it’s possible; maybe in good weather she gets up earlier and people are in better moods so they buy more stocks. But the most likely reason for this correlation is much simpler than that: She tried a whole bunch of different combinations until she found two things that correlated. At the usual significance level of 0.05, on average you need to try about 20 combinations of totally unrelated things before two of them will show up as correlated. (My guess is she used a number of different stock indexes and varied the starting and ending year. That’s a way to generate a surprisingly large number of degrees of freedom without it seeming like you’re doing anything particularly nefarious.)

But how do we know they aren’t actually causally related? Well, I suppose we don’t. Especially if the universe is ultimately deterministic and nonlocal (as I’ve become increasingly convinced by the results of recent quantum experiments), any two data sets could be causally related somehow. But the point is they don’t have to be; you can pick any randomly-generated datasets, pair them up in 20 different ways, and odds are, one of those ways will show a statistically significant correlation.

All of that is true, and important to understand. Finding a correlation between eating grapefruit and getting breast cancer, or between liking bitter foods and being a psychopath, does not necessarily mean that there is any real causal link between the two. If we can replicate these results in a bunch of other studies, that would suggest that the link is real; but typically, such findings cannot be replicated. There is something deeply wrong with the way science journalists operate; they like to publish the new and exciting findings, which 9 times out of 10 turn out to be completely wrong. They never want to talk about the really important and fascinating things that we know are true because we’ve been confirming them over hundreds of different experiments, because that’s “old news”. The journalistic desire to be new and first fundamentally contradicts the scientific requirement of being replicated and confirmed.

So, yes, it’s quite possible to have a correlation that tells you absolutely nothing about causation.

But this is exceptional. In most cases, correlation actually tells you quite a bit about causation.

And this is why I don’t like the adage; “imply” has a very different meaning in common speech, meaning merely to suggest or evoke. Almost everything you say implies all sorts of things in this broader sense, some more strongly than others, even though it may logically entail none of them.

Correlation does in fact suggest causation. Like any suggestion, it can be overridden. If we know that 20 different combinations were tried until one finally yielded a correlation, we have reason to distrust that correlation. If we find a correlation between A and B but there is no logical way they can be connected, we infer that it is simply an odd coincidence.

But when we encounter any given correlation, there are three other scenarios which are far more likely than mere coincidence: A causes B, B causes A, or some other factor C causes A and B. These are also not mutually exclusive; they can all be true to some extent, and in many cases are.

A great deal of work in science, and particularly in economics, is based upon using correlation to infer causation, and has to be—because there is simply no alternative means of approaching the problem.

Yes, sometimes you can do randomized controlled experiments, and some really important new findings in behavioral economics and development economics have been made this way. Indeed, much of the work that I hope to do over the course of my career is based on randomized controlled experiments, because they truly are the foundation of scientific knowledge. But sometimes, that’s just not an option.

Let’s consider an example: In my master’s thesis I found a strong correlation between the level of corruption in a country (as estimated by the World Bank) and the proportion of that country’s income which goes to the top 0.01% of the population. Countries that have higher levels of corruption also tend to have a larger proportion of income that accrues to the top 0.01%. That correlation is a fact; it’s there. There’s no denying it. But where does it come from? That’s the real question.

Could it be pure coincidence? Well, maybe; but when it keeps showing up in several different models with different variables included, that becomes unlikely. A single p < 0.05 will happen about 1 in 20 times by chance; but five in a row should happen less than 1 in 1 million times (assuming they’re independent, which, to be fair, they usually aren’t).

Could it be some artifact of the measurement methods? It’s possible. In particular, I was concerned about the possibility of Halo Effect, in which people tend to assume that something which is better (or worse) in one way is automatically better (or worse) in other ways as well. People might think of their country as more corrupt simply because it has higher inequality, even if there is no real connection. But it would have taken a very large halo bias to explain this effect.

So, does corruption cause income inequality? It’s not hard to see how that might happen: More corrupt individuals could bribe leaders or exploit loopholes to make themselves extremely rich, and thereby increase inequality.

Does inequality cause corruption? This also makes some sense, since it’s a lot easier to bribe leaders and manipulate regulations when you have a lot of money to work with in the first place.

Does something else cause both corruption and inequality? Also quite plausible. Maybe some general cultural factors are involved, or certain economic policies lead to both corruption and inequality. I did try to control for such things, but I obviously couldn’t include all possible variables.

So, which way does the causation run? Unfortunately, I don’t know. I tried some clever statistical techniques to try to figure this out; in particular, I looked at which tends to come first—the corruption or the inequality—and whether they could be used to predict each other, a method called Granger causality. Those results were inconclusive, however. I could neither verify nor exclude a causal connection in either direction. But is there a causal connection? I think so. It’s too robust to just be coincidence. I simply don’t know whether A causes B, B causes A, or C causes A and B.

Imagine trying to do this same study as a randomized controlled experiment. Are we supposed to create two societies and flip a coin to decide which one we make more corrupt? Or which one we give more income inequality? Perhaps you could do some sort of experiment with a proxy for corruption (cheating on a test or something like that), and then have unequal payoffs in the experiment—but that is very far removed from how corruption actually works in the real world, and worse, it’s prohibitively expensive to make really life-altering income inequality within an experimental context. Sure, we can give one participant $1 and the other $1,000; but we can’t give one participant $10,000 and the other $10 million, and it’s the latter that we’re really talking about when we deal with real-world income inequality. I’m not opposed to doing such an experiment, but it can only tell us so much. At some point you need to actually test the validity of your theory in the real world, and for that we need to use statistical correlations.

Or think about macroeconomics; how exactly are you supposed to test a theory of the business cycle experimentally? I guess theoretically you could subject an entire country to a new monetary policy selected at random, but the consequences of being put into the wrong experimental group would be disastrous. Moreover, nobody is going to accept a random monetary policy democratically, so you’d have to introduce it against the will of the population, by some sort of tyranny or at least technocracy. Even if this is theoretically possible, it’s mind-bogglingly unethical.

Now, you might be thinking: But we do change real-world policies, right? Couldn’t we use those changes as a sort of “experiment”? Yes, absolutely; that’s called a quasi-experiment or a natural experiment. They are tremendously useful. But since they are not truly randomized, they aren’t quite experiments. Ultimately, everything you get out of a quasi-experiment is based on statistical correlations.

Thus, abuse of the adage “Correlation does not imply causation” can lead to ignoring whole subfields of science, because there is no realistic way of running experiments in those subfields. Sometimes, statistics are all we have to work with.

This is why I like to say it a little differently:

Correlation does not prove causation. But correlation definitely can suggest causation.

Tax incidence revisited, part 2: How taxes affect prices

2015-11-142015-11-13 PNRJ core principles, public policy demand, equilibrium, labor, prices, salary, supply, tax incidence, taxation, taxes, wage

JDN 2457341

One of the most important aspects of taxation is also one of the most counter-intuitive and (relatedly) least-understood: Taxes are not externally applied to pre-existing exchanges of money. Taxes endogenously interact with the system of prices, changing what the prices will be and then taking a portion of the money exchanged.

The price of something “before taxes” is not actually the price you would pay for it if there had been no taxes on it. Your “pre-tax income” is not actually the income you would have had if there were no income or payroll taxes.

The most obvious case to consider is that of government employees: If there were no taxes, public school teachers could not exist, so the “pre-tax income” of a public school teacher is a meaningless quantity. You don’t “take taxes out” of a government salary; you decide how much money the government employee will actually receive, and then at the same time allocate a certain amount into other budgets based on the tax code—a certain amount into the state general fund, a certain amount into the Social Security Trust Fund, and so on. These two actions could in principle be done completely separately; instead of saying that a teacher has a “pre-tax salary” of $50,000 and is taxed 20%, you could simply say that the teacher receives $40,000 and pay $10,000 into the appropriate other budgets.

In fact, when there is a conflict of international jurisdiction this is sometimes literally what we do. Employees of the World Bank are given immunity from all income and payroll taxes (effectively, diplomatic immunity, though this is not usually how we use the term) based on international law, except for US citizens, who have their taxes paid for them by the World Bank. As a result, all World Bank salaries are quoted “after-tax”, that is, the actual amount of money employees will receive in their paychecks. As a result, a $120,000 salary at the World Bank is considerably higher than a $120,000 salary at Goldman Sachs; the latter would only (“only”) pay about $96,000 in real terms.

For private-sector salaries, it’s not as obvious, but it’s still true. There is actually someone who pays that “before-tax” salary—namely, the employer. “Pre-tax” salaries are actually a measure of labor expenditure (sometimes erroneously called “labor costs”, even by economists—but a true labor cost is the amount of effort, discomfort, stress, and opportunity cost involved in doing labor; it’s an amount of utility, not an amount of money). The salary “before tax” is the amount of money that the employer has to come up with in order to pay their payroll. It is a real amount of money being exchanged, divided between the employee and the government.

The key thing to realize is that salaries are not set in a vacuum. There are various economic (and political) pressures which drive employers to set different salaries. In the real world, there are all sorts of pressures that affect salaries: labor unions, regulations, racist and sexist biases, nepotism, psychological heuristics, employees with different levels of bargaining skill, employers with different concepts of fairness or levels of generosity, corporate boards concerned about public relations, shareholder activism, and so on.

But even if we abstract away from all that for a moment and just look at the fundamental economics, assuming that salaries are set at the price the market will bear, that price depends upon the tax system.

This is because taxes effectively drive a wedge between supply and demand.

Indeed, on a graph, it actually looks like a wedge, as you’ll see in a moment.

Let’s pretend that we’re in a perfectly competitive market. Everyone is completely rational, we all have perfect information, and nobody has any power to manipulate the market. We’ll even assume that we are dealing with hourly wages and we can freely choose the number of hours worked. (This is silly, of course; but removing this complexity helps to clarify the concept and doesn’t change the basic result that prices depend upon taxes.)

We’ll have a supply curve, which is a graph of the minimum price the worker is willing to accept for each hour in order to work a given number of hours. We generally assume that the supply curve slopes upward, meaning that people are willing to work more hours if you offer them a higher wage for each hour. The idea is that it gets progressively harder to find the time—it eats into more and more important alternative activities. (This is in fact a gross oversimplification, but it’ll do for now. In the real world, labor is the one thing for which the supply curve frequently bends backward.)

We’ll also have a demand curve, which is a graph of the maximum price the employer is willing to pay for each hour, if the employee works that many hours. We generally assume that the demand curve slopes downward, meaning that the employer is willing to pay less for each hour if the employee works more hours. The reason is that most activities have diminishing marginal returns, so each extra hour of work generally produces less output than the previous hour, and is therefore not worth paying as much for. (This too is an oversimplification, as I discussed previously in my post on the Law of Demand.)

Put these two together, and in a competitive market the price will be set at the point at which supply is equal to demand, so that the very last hour of work was worth exactly what the employer paid for it. That last hour is just barely worth it to the employer, and just barely worth it to the worker; any additional time would either be too expensive for the employer or not lucrative enough for the worker. But for all the previous hours, the value to the employer is higher than the wage, and the cost to the worker is lower than the wage. As a result, both the employer and the worker benefit.

But now, suppose we implement a tax. For concreteness, suppose the previous market-clearing wage was $20 per hour, the worker was working 40 hours, and the tax is 20%. If the employer still offers a wage of $20 for 40 hours of work, the worker is no longer going to accept it, because they will only receive $16 per hour after taxes, and $16 isn’t enough for them to be willing to work 40 hours. The worker could ask for a pre-tax wage of $25 so that the after-tax wage would be $20, but then the employer will balk, because $25 per hour is too expensive for 40 hours of work.

In order to restore the balance (and when we say “equilibrium”, that’s really all we mean—balance), the employer will need to offer a higher pre-tax wage, which means they will demand fewer hours of work. The worker will then be willing to accept a lower after-tax wage for those reduced hours.

In effect, there are now two prices at work: A supply price, the after-tax wage that the worker receives, which must be at or above the supply curve; and a demand price, the pre-tax wage that the employer pays, which must be at or below the demand curve. The difference between those two prices is the tax.

In this case, I’ve set it up so that the pre-tax wage is $22.50, the after-tax wage is $18, and the amount of the tax is $4.50 or 20% of $22.50. In order for both the employer and the worker to accept those prices, the amount of hours worked has been reduced to 35.

As a result of the tax, the wage that we’ve been calling “pre-tax” is actually higher than the wage that the worker would have received if the tax had not existed. This is a general phenomenon; it’s almost always true that your “pre-tax” wage or salary overestimates what you would have actually gotten if the tax had not existed. In one extreme case, it might actually be the same; in another extreme case, your after-tax wage is what you would have received and the “pre-tax” wage rises high enough to account for the entirety of the tax revenue. It’s not really “pre-tax” at all; it’s the after-tax demand price.

Because of this, it’s fundamentally wrongheaded for people to complain that taxes are “taking your hard-earned money”. In all but the most exceptional cases, that “pre-tax” salary that’s being deducted from would never have existed. It’s more of an accounting construct than anything else, or like I said before a measure of labor expenditure. It is generally true that your after-tax salary is lower than the salary you would have gotten without the tax, but the difference is generally much smaller than the amount of the tax that you see deducted. In this case, the worker would see $4.50 per hour deducted from their wage, but in fact they are only down $2 per hour from where they would have been without the tax. And of course, none of this includes the benefits of the tax, which in many cases actually far exceed the costs; if we extended the example, it wouldn’t be hard to devise a scenario in which the worker who had their wage income reduced received an even larger benefit in the form of some public good such as national defense or infrastructure.

To truly honor veterans, end war

2015-11-112015-11-13 PNRJ core principles An Lushan Rebellion, China, death, drone strikes, Germany, India, ISIS, Japan, Long Peace, military, Nassim Nicholas Taleb, North Korea, nuclear weapons, Pakistan, Poland, South Africa, Steven Pinker, suicide, veteran, Veterans' Day, war, Woodrow Wilson, World War 2

JDN 2457339 EST 20:00 (Nov 11, 2015)

Today is Veterans’ Day, on which we are asked to celebrate the service of military veterans, particularly those who have died as a result of war. We tend to focus on those who die in combat, but actually these have always been relatively uncommon; throughout history, most soldiers have died later of their wounds or of infections. More recently as a result of advances in body armor and medicine, actually relatively few soldiers die even of war wounds or infections—instead, they are permanently maimed and psychologically damaged, and the most common way that war kills soldiers now is by making them commit suicide.

Even adjusting for the fact that soldiers are mostly young men (the group of people most likely to commit suicide), military veterans still have about 50 excess suicides per million people per year, for a total of about 300 suicides per million per year. Using the total number, that’s over 8000 veteran suicides per year, or 22 per day. Using only the excess compared to men of the same ages, it’s still an additional 1300 suicides per year.

While the 14-years-and-counting Afghanistan War has killed 2,271 American soldiers and the 11-year Iraq War has killed 4,491 American soldiers directly (or as a result of wounds), during that same time period from 2001 to 2015 there have been about 18,000 excess suicides as a result of the military—excess in the sense that they would not have occurred if those men had been civilians. Altogether that means there would be nearly 25,000 additional American soldiers alive today were it not for these two wars.

War does not only kill soldiers while they are on the battlefield—indeed, most of the veterans it kills die here at home.

There is a reason Woodrow Wilson chose November 11 as the date for Veterans’ Day: It was on this day in 1918 that World War 1, up to that point the war that had caused the most deaths in human history, was officially ended. Sadly, it did not remain the deadliest war, but was surpassed by World War 2 a generation later. Fortunately, no other war has ever exceeded World War 2—at least, not yet.

We tend to celebrate holidays like this with a lot of ritual and pageantry (or even in the most inane and American way possible, with free restaurant meals and discounts on various consumer products), and there’s nothing inherently wrong with that. Nor is there anything wrong with taking a moment to salute the flag or say “Thank you for your service.” But that is not how I believe veterans should be honored. If I were a veteran, that is not how I would want to be honored.

We are getting much closer to how I think they should be honored when the White House announces reforms at Veterans’ Affairs hospitals and guaranteed in-state tuition at public universities for families of veterans—things that really do in a concrete and measurable way improve the lives of veterans and may even save some of them from that cruel fate of suicide.

But ultimately there is only one way that I believe we can truly honor veterans and the spirit of the holiday as Wilson intended it, and that is to end war once and for all.

Is this an ambitious goal? Absolutely. But is it an impossible dream? I do not believe so.

In just the last half century, we have already made most of the progress that needed to be made. In this brilliant video animation, you can see two things: First, the mind-numbingly horrific scale of World War 2, the worst war in human history; but second, the incredible progress we have made since then toward world peace. It was as if the world needed that one time to be so unbearably horrible in order to finally realize just what war is and why we need a better way of solving conflicts.

This is part of a very long-term trend in declining violence, for a variety of reasons that are still not thoroughly understood. In simplest terms, human beings just seem to be getting better at not killing each other.

Nassim Nicholas Taleb argues that this is just a statistical illusion, because technologies like nuclear weapons create the possibility of violence on a previously unimaginable scale, and it simply hasn’t happened yet. For nuclear weapons in particular, I think he may be right—the consequences of nuclear war are simply so catastrophic that even a small risk of it is worth paying almost any price to avoid.

Fortunately, nuclear weapons are not necessary to prevent war: South Africa has no designs on attacking Japan anytime soon, but neither has nuclear weapons. Germany and Poland lack nuclear arsenals and were the first countries to fight in World War 2, but now that both are part of the European Union, war between them today seems almost unthinkable. When American commentators fret about China today it is always about wage competition and Treasury bonds, not aircraft carriers and nuclear missiles. Conversely, North Korea’s acquisition of nuclear weapons has by no means stabilized the region against future conflicts, and the fact that India and Pakistan have nuclear missiles pointed at one another has hardly prevented them from killing each other over Kashmir. We do not need nuclear weapons as a constant threat of annihilation in order to learn to live together; political and economic ties achieve that goal far more reliably.

And I think Taleb is wrong about the trend in general. He argues that the only reason violence is declining is that concentration of power has made violence rarer but more catastrophic when it occurs. Yet we know that many forms of violence which used to occur no longer do, not because of the overwhelming force of a Leviathan to prevent them, but because people simply choose not to do them anymore. There are no more gladiator fights, no more cat-burnings, no more public lynchings—not because of the expansion in government power, but because our society seems to have grown out of that phase.

Indeed, what horrifies us about ISIS and Boko Haram would have been considered quite normal, even civilized, in the Middle Ages. (If you’ve ever heard someone say we should “bring back chivalry”, you should explain to them that the system of knight chivalry in the 12^th century had basically the same moral code as ISIS today—one of the commandments Gautier’s La Chevalerie attributes as part of the chivalric code is literally “Thou shalt make war against the infidel without cessation and without mercy.”) It is not so much that they are uniquely evil by historical standards, as that we grew out of that sort of barbaric violence awhile ago but they don’t seem to have gotten the memo.

In fact, one thing people don’t seem to understand about Steven Pinker’s argument about this “Long Peace” is that it still works if you include the world wars. The reason World War 2 killed so many people was not that it was uniquely brutal, nor even simply because its weapons were more technologically advanced. It also had to do with the scale of integration—we called it a single war even though it involved dozens of countries because those countries were all united into one of two sides, whereas in centuries past that many countries could be constantly fighting each other in various combinations but it would never be called the same war. But the primary reason World War 2 killed the largest raw number of people was simply because the world population was so much larger. Controlling for world population, World War 2 was not even among the top 5 worst wars—it barely makes the top 10. The worst war in history by proportion of the population killed was almost certainly the An Lushan Rebellion in 8 ^th century China, which many of you may not even have heard of until today.

Though it may not seem so as ISIS kidnaps Christians and drone strikes continue, shrouded in secrecy, we really are on track to end war. Not today, not tomorrow, maybe not in any of our lifetimes—but someday, we may finally be able to celebrate Veterans’ Day as it was truly intended: To honor our soldiers by making it no longer necessary for them to die.

Tax Incidence Revisited, Part 1: The downside of taxes

2015-11-082015-11-08 PNRJ core principles, public policy alcohol, alcohol tax, crime, deadweight loss, Denmark, externalities, Jeb!, Laffer Curve, land tax, lead, Marco Rubio, Pigovian tax, Reaganomics, supply-side, tax incidence, taxation, taxes, trickle-down, voodoo economics

JDN 2457345 EST 22:02

As I was writing this, it was very early (I had to wake up at 04:30) and I was groggy, because we were on an urgent road trip to Pennsylvania for the funeral of my aunt who died quite suddenly a few days ago. I have since edited this post more thoroughly to minimize the impact of my sleep deprivation upon its content. Actually maybe this is a good thing; the saying goes, “write drunk, edit sober” and sleep deprivation and alcohol have remarkably similar symptoms, probably because alcohol is GABA-ergic and GABA is involved in sleep regulation.

Awhile ago I wrote a long post on tax incidence, but the primary response I got was basically the online equivalent of a perplexed blank stare. Struck once again by the Curse of Knowledge, I underestimated the amount of background knowledge necessary to understand my explanation. But tax incidence is very important for public policy, so I really would like to explain it.

Therefore I am now starting again, slower, in smaller pieces. Today’s piece is about the downsides of taxation in general, why we don’t just raise taxes as high as we feel like and make the government roll in dough.

To some extent this is obvious; if income tax were 100%, why would anyone bother working for a salary? You might still work for fulfillment, or out of a sense of duty, or simply because you enjoy what you do—after all, most artists and musicians are hardly in it for the money. But many jobs are miserable and not particularly fulfilling, yet still need to get done. How many janitors or bus drivers work purely for the sense of fulfillment it gives them? Mostly they do it to pay the bills—and if income tax were 100%, it wouldn’t anymore. The formal economy would basically collapse, and then nobody would end up actually paying that 100% tax—so the government would actually get very little revenue, if any.

At the other end of the scale, it’s kind of obvious that if your taxes are all 0% you don’t get any revenue. This is actually more feasible than it may sound; provided you spend only a very small amount (say, 4% of GDP, though that’s less than any country actually spends—maybe you could do 6% like Bangladesh) and you can still get people to accept your currency, you could, in principle, have a government that funds its spending entirely by means of printing money, and could do this indefinitely. In practice, that has never been done, and the really challenging part is getting people to accept your money if you don’t collect taxes in it. One of the more counter-intuitive aspects of modern monetary theory (or perhaps I should capitalize it, Modern Monetary Theory, though the part I agree with is not that different from standard Keynesian theory) is that taxation is the primary mechanism by which money acquires its value.

And then of course with intermediate tax rates such as 20%, 30%, and 50% that actual countries actually use, we do get some positive amount of revenue.

Everything I’ve said so far may seem pretty obvious. Yeah, usually taxes raise revenue, but if you taxed at 0% or 100% they wouldn’t; so what?

Well, this leads to quite an important result. Assuming that tax revenue is continuous (which isn’t quite true, but since we can collect taxes in fractions of a percent and pay in pennies, it’s pretty close), it follows directly from the Extreme Value Theorem that there is in fact a revenue-maximizing tax rate. Both below and above that tax rate, the government takes in less total money. These theorems don’t tell us what the revenue-maximizing rate is; but they tell us that it must exist, somewhere between 0% and 100%.

Indeed, it follows that there is what we call the Laffer Curve, a graph of tax revenue as a function of tax rate, and it is in fact a curve, as opposed to the straight line it would be if taxes had no effect on the rest of the economy.

Very roughly, it looks something like this (the blue curve is my sketch of the real-world Laffer curve, while the red line is what it would be if taxes had no distortionary effects):

Now, the Laffer curve has been abused many times; in particular, it’s been used to feed into the “trickle-down” “supply-side” Reaganomics that has been rightly derided as “voodoo economics” by serious economists. Jeb Bush (or should I say, Jeb!) and Marco Rubio would have you believe that we are on the right edge of the Laffer curve, and we could actually increase tax revenue by cutting taxes, particularly on capital gains and incomes at the top 1%; that’s obviously false. We tried that, it didn’t work. Even theoretically we probably should have known that it wouldn’t; but now that we’ve actually done the experiment and it failed, there should be no serious doubt anymore.

No, we are on the left side of the Laffer curve, where increasing taxes increases revenue, much as you’d intuitively expect. It doesn’t quite increase one-to-one, because adding more taxes does make the economy less efficient; but from where we currently stand, a 1% increase in taxes leads to about a 0.9% increase in revenue (actually estimated as between 0.78% and 0.99%).

Denmark may be on the right side of the Laffer curve, where they could raise more revenue by decreasing tax rates (even then I’m not so sure). But Denmark’s tax rates are considerably higher than ours; while in the US we pay about 2 7% of GDP in taxes, folks in Denmark pay 49% of GDP in taxes.

The fact remains, however, that there is a Laffer curve, and no serious economist would dispute this. Increasing taxes does in fact create distortions in the economy, and as a result raising tax rates does not increase revenue in a one-to-one fashion. When calculating the revenue from a new tax, you must include not only the fact that the government will get an increased portion, but also that the total amount of income will probably decrease.

Now, I must say probably, because it does depend on what exactly you are taxing. If you tax something that is perfectly inelastic—the same amount of it is going to be made and sold no matter what—then total income will remain exactly the same after the tax. It may be distributed differently, but the total won’t change. This is one of the central justifications for a land tax; land is almost perfectly inelastic, so taxing it allows us to raise revenue without reducing total income.

In fact, there are certain kinds of taxes which increase total income, which makes them basically no-brainer taxes that should always be implemented if at all feasible. These are Pigovian taxes, which are taxes on products with negative externalities; when a product causes harm to other people (the usual example is pollution of air and water), taxing that product equal to the harm caused provides a source of government revenue that also increases the efficiency of the economy as a whole. If we had a tax on carbon emissions that was used to fund research into sustainable energy, this would raise our total GDP in the long run. Taxes on oil and natural gas are not “job killing”; they are job creating. This is why we need a carbon tax, a higher gasoline tax, and a financial transaction tax (to reduce harmful speculation); it’s also why we already have high taxes on alcohol and tobacco.

The alcohol tax is one of the great success stories of Pigouvian taxation.The alcohol tax is actually one of the central factors holding our crime rate so low right now. Another big factor is overall economic growth and anti-poverty programs. The most important factor, however, is lead, or rather the lack thereof; environmental regulations reducing pollutants like lead and mercury from the environment are the leading factor in reducing crime rates over the last generation. Yes, that’s right—our fall in crime had little to do with state police, the FBI, the DEA, or the ATF; our most effective crime-fighting agency is the EPA. This is really not that surprising, as a cognitive economist. Most crime is impulsive and irrational, or else born of economic desperation. Rational crime that it would make sense to punish harshly as a deterrent is quite rare (well, except for white-collar crime, which of course we don’t punish harshly enough—I know I harp on this a lot, but HSBC laundered money for terrorists). Maybe crime would be more common if we had no justice system in place at all, but making our current system even harsher accomplishes basically nothing. Far better to tax the alcohol that leads good people to bad decisions.

It also matters whom you tax, though one of my goals in this tax incidence series is to explain why that doesn’t mean quite what most people think it does. The person who writes the check to the government is not necessarily the person who really pays the tax. The person who really pays is the one whose net income ends up lower after the tax is implemented. Often these are the same person; but often they aren’t, for fundamental reasons I’m hoping to explain.

For now, it’s worth pointing out that a tax which primarily hits the top 1% is going to have a very different impact on the economy than one which hits the entire population. Because of the income and substitution effects, poor people tend to work less as their taxes go up, but rich people tend to work more. Even within income brackets, a tax that hits doctors and engineers is going to have a different effect than a tax that hits bankers and stock traders, and a tax that hits teachers is going to have a different effect than a tax that hits truck drivers. A tax on particular products or services will reduce demand for those products or services, which is good if that’s what you’re trying to do (such as alcohol) but not so good if it isn’t.

So, yes, there are cases where raising taxes can actually increase, or at least not reduce, total income. These are the exception, however; as a general rule, in a Pirate Code sort of way, taxes reduce total income. It’s not simply that income goes down for everyone but the government (which would again be sort of obvious); income goes down for everyone including the government. The difference is simply lost, wasted away by a loss in economic efficiency. We call that difference deadweight loss, and for a poorly-designed tax it can actually far exceed the revenue received.

I think an extreme example may help to grasp the intuition: Suppose we started taxing cars at 200,000%, so that a typical new car costs something like $40 million with taxes. (That’s not a Lamborghini, mind you; that’s a Honda Accord.) What would happen? Nobody is going to buy cars anymore. Overnight, you’ve collapsed the entire auto industry. Dozens of companies go bankrupt, thousands of employees get laid off, the economy immediately falls into recession. And after all that, your car tax will raise no revenue at all, because not a single car will sell. It’s just pure deadweight loss.

That’s an intentionally extreme example; most real-world taxes in fact create less deadweight loss than they raise in revenue. But most real-world taxes do in fact create deadweight loss, and that’s a good reason to be concerned about any new tax.

In general, higher taxes create lower total income, or equivalently higher deadweight loss. All other things equal, lower taxes are therefore better.

What most Americans don’t seem to quite grasp is that all other things are not equal. That tax revenue is central to the proper functioning of our government and our monetary system. We need a certain amount of taxes in order to ensure that we can maintain a stable currency and still pay for things like Medicare, Social Security, and the Department of Defense (to name our top three budget items).

Alternatively, we could not spend so much on those things, and that is a legitimate question of public policy. I personally think that Medicare and Social Security are very good things (and I do have data to back that up—Medicare saves thousands of lives), but they aren’t strictly necessary for basic government functioning; we could get rid of them, it’s just that it would be a bad idea. As for the defense budget, some kind of defense budget is necessary for national security, but I don’t think I’m going out on a very big limb here when I say that one country making 40% of all world military spending probably isn’t.

We can’t have it both ways; if you want Medicare, Social Security, and the Department of Defense, you need to have taxes. “Cutting spending” always means cutting spending on something—so what is it you want to cut? A lot of people seem to think that we waste a huge amount of money on pointless bureaucracy, pork-barrel spending, or foreign aid; but that’s simply not true. All government administration is less than 1% of the budget, and most of it is necessary; earmarks are also less than 1%; foreign aid is also less than 1%. Since our deficit is about 15% of spending, we could eliminate all of those things and we’d barely put a dent in it.

Americans don’t like taxes; I understand that. It’s basically one of our founding principles, in fact, though “No taxation without representation” seems to have mutated of late into simply “No taxation”, or maybe “Read my lips, no new taxes!” It’s never pleasant to see that chunk taken out of your paycheck before you even get it. (Though one thing I hope to explain in this series is that these figures are really not very meaningful; there’s no particular reason to think you’d have made the same gross salary if those taxes hadn’t been present.)

There are in fact sound economic reasons to keep taxes low. The Laffer Curve is absolutely a real thing, even though most of its applications are wrong. But sometimes we need taxes to be higher, and that’s a tradeoff we have to make.We need to have a serious public policy discussion about where our priorities lie, not keep trading sound-bytes about “cutting wasteful spending” and “job-killing tax hikes”.

Just give people money!

2015-11-05 PNRJ core principles, critique of neoclassical economics, development economics, public policy abolish poverty, altruism, basic income, cash transfer, inequality, justice, Maslow, Nelson Mandela, Permanent Fund Dividend, poverty, redistribution, self-interest, wealth

JDN 2457332 EDT 17:02.

Today is the Fifth of November, on which a bunch of people who liked a Hollywood movie start posting images in support of a fanatical religious terrorist in his plot to destroy democracy in the United Kingdom a few centuries ago. It’s really weird, but I’m not particularly interested in that.

Instead I’d like to talk about the solution to poverty, which we’ve known for a long time—in fact, it’s completely obvious—and yet have somehow failed to carry out. Many people doubt that it even works, not based on the empirical evidence, but because it just feels like it can’t be right, like it’s so obvious that surely it was tried and didn’t work and that’s why we moved on to other things. When you first tell a kindergartner that there are poor people in the world, that child will very likely ask: “Why don’t we just give them some money?”

Why not indeed?

Formally this is called a “direct cash transfer”, and it comes in many different variants, but basically they run along a continuum from unconditional—we just give it to everybody, no questions asked—to more and more conditional—you have to be below a certain income, or above a certain age, or have kids, or show up at our work program, or take a drug test, etc. The EU has a nice little fact sheet about the different types of cash transfer programs in use.

Actually, I’d argue that at the very far extreme is government salaries—the government will pay you $40,000 per year, provided that you teach high school every weekday. We don’t really think of that as a “conditional cash transfer” because it involves you providing a useful service (and is therefore more like an ordinary, private-sector salary), but many of the conditions imposed on cash transfers actually have this sort of character—we want people to do things that we think are useful to society, in order to justify us giving them the money. It really seems to be a continuum, from just giving money to everyone, to giving money to some people based on them doing certain things, to specifically hiring people to do something.

Social programs in different countries can be found at different places on this continuum. In the United States, our programs are extremely conditional, and also the total amount we give out is relatively small. In Europe, programs are not as conditional—though still conditional—and they give out more. And sure enough, after-tax poverty in Europe is considerably lower, even though before-tax poverty is about the same.

In fact, the most common way to make transfers conditional is to make them “in-kind”; instead of giving you money, we give you something—healthcare, housing, food. Sometimes this makes sense; actually I think for healthcare it makes the most sense, because price signals don’t work in a market as urgent and inelastic as healthcare (that is, you don’t shop around for an emergency room—in fact, people don’t even really shop around for a family doctor). But often it’s simply a condition we impose for political reasons; we don’t want those “lazy freeloaders” to do anything else with the money that we wouldn’t like, such as buying alcohol or gambling. Even poor people in India buy into this sort of reasoning. Nevermind that they generally don’t do that, or that they could just shift away spending they would otherwise be making (warning: technical economics paper within) to do those things anyway—it’s the principle of the thing.

Direct cash transfers not only work—they work about as well as the best things we’ve tried. Spending on cash transfers is about as cost-effective as spending on medical aid and malaria nets.

Other than in experiments (the largest of which I’m aware of was a town in Canada, unless you count Alaska’s Permanent Fund Dividend, which is unconditional but quite small), we have never really tried implementing a fully unconditional cash transfer system. “Too expensive” is usually the complaint, and it would indeed be relatively expensive (probably greater than all of what we currently spend on Social Security and Medicare, which are two of our biggest government budget items). Implementing a program with a cost on the order of $2 trillion per year is surely not something to be done lightly. But it would have one quite substantial benefit: It would eliminate poverty in the United States immediately and forever.

This is why I really like the “abolish poverty” movement; we must recognize that at our current level of economic development, poverty is no longer a natural state, a complex problem to solve. It is a policy decision that we are making. We are saying, as a society, that we would rather continue to have poverty than spend that $2 trillion per year, about 12% of our $17.4 trillion GDP. We are saying that we’d rather have people who are homeless and starving than lose 12 cents of every dollar we make. (To be fair, if we include the dynamic economic impact of this tax-and-transfer system it might actually turn out to be more than that; but it could in fact be less—the increased spending would boost the economy, just as the increased taxes would restrain it—and seems very unlikely to be more than 20% of GDP.)

For most of human history—and in most countries today—that is not the case. India could not abolish poverty immediately by a single tax policy; nor could China. Probably not Brazil either. Maybe Greece could do it, but then again maybe not. But Germany could; the United Kingdom could; France could; and we could in the United States. We have enough wealth now that with a moderate increase in government spending we could create an economic floor below which no person could fall. It is incumbent upon us at the very least to justify why we don’t.

I have heard it said that poverty is not a natural condition, but the result of human action. Even Nelson Mandela endorsed this view. This is false, actually. In general, poverty is the natural condition of all life forms on Earth (and probably all life forms in the universe). Natural selection evolves us toward fitting as many gene-packages into the environment as possible, not toward maximizing the happiness of the sentient beings those gene-packages may happen to be. To a first approximation, all life forms suffer in poverty.

We live at a unique time in human history; for no more than the last century—and perhaps not even that—we have actually had so much wealth that we could eliminate poverty by choice. For hundreds of thousands of years human beings toiled in poverty because there was no such choice. Perhaps good policy in Greece could end poverty today, but it couldn’t have during the reign of Pericles. Good policy in Italy could end poverty now, but not when Caesar was emperor. Good policy in the United Kingdom could easily end poverty immediately, but even under Queen Victoria that wasn’t feasible.

Maybe that’s why we aren’t doing it? Our cultural memory was forged in a time decades or centuries ago, before we had this much wealth to work with. We speak of “end world hunger” in the same breath as “cure cancer” or “conquer death”, a great dream that has always been impossible and perhaps still is—but in fact we should speak of it in the same breath as “split the atom” and “land on the Moon”, seminal achievements that our civilization is now capable of thanks to economic and technological revolution.

Capitalism also seems to have a certain momentum to it; once you implement a market economy that maximizes wealth by harnessing self-interest, people seem to forget that we are fundamentally altruistic beings. I may never forget that economist who sent me an email with “altruism” in scare quotes, as though it was foolish (or at best imprecise) to say that human beings care about one another. But in fact we are the most altruistic species on Earth, without question, in a sense so formal and scientific it can literally be measured quantitatively.

There are real advantages to harnessing self-interest—not least, I know my own interests considerably better than I know yours, no matter who you are—and that is part of how we have achieved this great level of wealth (though personally I think science, democracy, and the empowerment of women are the far greater causes of our prosperity). But we must not let it forget us why we wanted to have wealth in the first place: Not to concentrate power in a handful of individuals who will pass it on to their heirs; not to “maximize work incentives”; not to give us the fanciest technological gadgets. The reason we wanted to have wealth was so that we could finally free ourselves from the endless toil that was our lot by birth and that of all other beings—to let us finally live, instead of merely survive. There is a peak to Maslow’s pyramid, and we could stand there now, together; but we must find the will to give up that 12 cents of every dollar.

How about we listen to the Nobel Laureate when we set our taxes?

2015-10-252017-10-08 PNRJ core principles, financial fraud, inequality, macroeconomics, public policy Apple, Bernie Sanders, Bill Clinton, capital, capital gains, Center for American Progress, corporate welfare, debt, debt crisis, deficit, externalities, finance, fiscal policy, Henry George, high-frequency trading, income tax, Jon Stewart, Krugman, Marco Rubio, multiplier, Obama, progressive taxation, puppies and rainbows, reform, sales tax, Stiglitz, subsidy, tax expenditure, taxation, Tim Cook, unemployment, VAT, voodoo economics

JDN 2457321 EDT 11:20

I know I’m going out on a limb here, but I think it would generally be a good thing if we based our tax system on the advice of Nobel Laureate economists. Joseph Stiglitz wrote a tax policy paper for the Roosevelt Institution last year that describes in detail how our tax system could be reformed to simultaneously restore economic growth, reduce income inequality, promote environmental sustainability, and in the long run even balance the budget. What’s more, he did the math (I suppose Nobel Laureate economists are known for that), and it looks like his plan would actually work.

The plan is good enough that I think it’s worth going through in some detail.

He opens by reminding us that our “debt crisis” is of our own making, the result of politicians (and voters) who don’t understand economics:

“But we should be clear that these crises – which have resulted in a government shutdown and a near default on the national debt – are not economic but political. The U.S. is not like Greece, unable to borrow to fund its debt and deficit. Indeed, the U.S. has been borrowing at negative real interest rates.”

Stiglitz pulls no punches against bad policies, and isn’t afraid to single out conservatives:

“We also show that some of the so-called reforms that conservatives propose would be counterproductive – they could simultaneously reduce growth and economic welfare and increase unemployment and inequality. It would be better to have no reform than these reforms.”

A lot of the news media keep trying to paint Bernie Sanders as a far-left radical candidate (like this article in Politico calling his hometown the “People’s Republic of Burlington”), because he says things like this: “in recent years, over 99 percent of all new income generated in the economy has gone to the top 1 percent.”

But the following statement was not said by Bernie Sanders, it was said by Joseph Stiglitz, who I will remind you one last time is a world-renowned Nobel Laureate economist:

“The weaknesses in the labor market are reflected in low wages and stagnating incomes. That helps explain why 95 percent of the increase in incomes in the three years after the recovery officially began went to the upper 1 percent. For most Americans, there has been no recovery.”

It was also Stiglitz who said this:

“The American Dream is, in reality, a myth. The U.S. has some of the worst inequality across generations (social mobility) among wealthy nations. The life prospects of a young American are more dependent on the income and education of his parents than in other advanced countries.”

In this country, we have reached the point where policies supported by the analysis of world-renowned economists is considered far-left radicalism, while the “mainstream conservative” view is a system of tax policy that is based on pure fantasy, which has been called “puppies and rainbows” by serious policy analysts and “voodoo economics” by yet another Nobel Laureate economist. A lot of very smart people don’t understand what’s happening in our political system, and want “both sides” to be “equally wrong”, but that is simply not the case: Basic facts of not just social science (e.g. Keynesian monetary policy), but indeed natural science (evolutionary biology, anthropogenic climate change) are now considered “political controversies” because the right wing doesn’t want to believe them.

But let’s get back to the actual tax plan Stiglitz is proposing. He is in favor of raising some taxes and lowering others, spending more on some things and less on other things. His basic strategy is actually quite simple: Raise taxes with low multipliers and cut taxes with high multipliers. Raise spending with high multipliers and cut spending with low multipliers.

“While in general taxes take money out of the system, and therefore have a deflationary bias, some taxes have a larger multiplier than others, i.e. lead to a greater reduction in aggregate demand per dollar of revenue raised. Taxes on the rich and superrich, who save a large fraction of their income, have the least adverse effect on aggregate demand. Taxes on lower income individuals have the most adverse effect on aggregate demand.”

In other words, by making the tax system more progressive, we can directly stimulate economic growth while still increasing the amount of tax revenue we raise. And of course we have plenty of other moral and economic reasons to prefer progressive taxation.

Stiglitz tears apart the “job creator” myth:

“It is important to dispel a misunderstanding that one often hears from advocates of lower taxes for the rich and corporations, which contends that the rich are the job producers, and anything that reduces their income will reduce their ability and incentive to create jobs. First, at the current time, it is not lack of funds that is holding back investment. It is not even a weak and dysfunctional financial sector. America’s large corporations are sitting on more than $2 trillion in cash. What is holding back investment, especially by large corporations, is the lack of demand for their products.”

Stiglitz talks about two principles of taxation to follow:

First is the Generalized Henry George Principle, that we should focus taxes on things that are inelastic, meaning their supply isn’t likely to change much with the introduction of a tax. Henry George favored taxing land, which is quite inelastic indeed. The reason we do this is to reduce the economic distortions created by a tax; the goal is to collect revenue without changing the number of real products that are bought and sold. We need to raise revenue and we want to redistribute income, but we want to do it without creating unnecessary inefficiencies in the rest of the economy.

Second is the Generalized Polluter Pays Principle, that we should tax things that have negative externalities—effects on other people that are harmful. When a transaction causes harm to others who were not party to the transaction, we should tax that transaction in an amount equal to the harm that it would cause, and then use that revenue to offset the damage. In effect, if you hurt someone else, you should have to pay to clean up your own mess. This makes obvious moral sense, but it also makes good economic sense; taxing externalities can improve economic efficiency and actually make everyone better off. The obvious example is again pollution (the original Polluter Pays Principle), but there are plenty of other examples as well.

Stiglitz of course supports taxes on pollution and carbon emissions, which really should be a no-brainer. They aren’t just good for the environment, they would directly increase economic efficiency. The only reason we don’t have comprehensive pollution taxes (or something similar like cap-and-trade) is again the political pressure of right-wing interests.

Stiglitz focuses in particular on the externalities of the financial system, the boom-and-bust cycle of bubble, crisis, crash that has characterized so much of our banking system for generations. With a few exceptions, almost every major economic crisis has been preceded by some sort of breakdown of the financial system (and typically widespread fraud by the way). It is not much exaggeration to say that without Wall Street there would be no depressions. Externalities don’t get a whole lot bigger than that.

Stiglitz proposes a system of financial transaction taxes that are designed to create incentives against the most predatory practices in finance, especially the high-frequency trading in which computer algorithms steal money from the rest of the economy thousands of times per second. Even a 0.01% tax on each financial transaction would probably be enough to eliminate this particular activity.

He also suggests the implementation of “bonus taxes” which disincentivize paying bonuses, which could basically be as simple as removing the deductions placed during the Clinton administration (in a few years are we going to have to say “the first Clinton administration”?) that exempt “performance-based pay” from most forms of income tax. All pay is performance-based, or supposed to be. There should be no special exemption for bonuses and stock options.

Stiglitz also proposes a “bank rescue fund” which would be something like an expansion of the FDIC insurance that banks are already required to have, but designed as catastrophe insurance for the whole macroeconomy. Instead of needing bailed out from general government funds, banks would only be bailed out from a pool of insurance funds they paid in themselves. This could work, but honestly I think I’d rather reduce the moral hazard even more by saying that we will never again bail out banks directly, but instead bail out consumers and real businesses. This would probably save banks anyway (most people don’t default on debts if they can afford to pay them), and if it doesn’t, I don’t see why we should care. The only reason banks exist is to support the real economy; if we can support the real economy without them, they deserve to die. That basic fact seems to have been lost somewhere along the way, and we keep talking about how to save or stabilize the financial system as if it were valuable unto itself.

Stiglitz also proposes much stricter regulations on credit cards, which would require them to charge much lower transaction fees and also pay a portion of their transaction revenue in taxes. I think it’s fair to ask whether we need credit cards at all, or if there’s some alternative banking system that would allow people to make consumer purchases without paying 20% annual interest. (It seems like there ought to be, doesn’t it?)

Next Stiglitz gets to his proposal to reform the corporate income tax. Like many of us, he is sick of corporations like Apple and GE with ten and eleven-figure profits paying little or no taxes by exploiting a variety of loopholes. He points out some of the more egregious ones, like the “step up of basis at death” which allows inherited capital to avoid taxation (personally, I think both morally and economically the optimal inheritance tax rate is 100%!), as well as the various loopholes on offshore accounting which allow corporations to design and sell their products in the US, even manufacture them here, and pay taxes as if all their work were done in the Cayman Islands. He also points out that the argument that corporate taxes disincentivize investment is ridiculous, because most investment is financed by corporate bonds which are tax-deductible.

Stiglitz departs from most other economists in that he actually proposes raising the corporate tax rate itself. Most economists favor cutting the rate on paper, then closing the loopholes to ensure that the new rate is actually paid. Stiglitz says this is not enough, and we must both close the loopholes and increase the rate.

I’m actually not sure I agree with him on this; the incidence of corporate taxes is not very well-understood, and I think there’s a legitimate worry that taxing Apple will make iPhones more expensive without actually taking any money from Tim Cook. I think it would be better to get rid of the corporate tax entirely and then dramatically raise the marginal rates on personal income, including not only labor income but also all forms of capital income. Instead of taxing Apple hoping it will pass through to Tim Cook, I say we just tax Tim Cook. Directly tax his $4 million salary and $70 million in stock options.

Stiglitz does have an interesting proposal to introduce “rent-seeking” taxes that specifically apply to corporations which exercise monopoly or oligopoly power. If you can actually get this to work, it’s very clever; you could actually create a market incentive for corporations to support their own competition—and not in the sense of collusion but in the sense of actually trying to seek out more competitive markets in order to avoid the monopoly tax. Unfortunately, Stiglitz is a little vague on how we’d actually pull that off.

One thing I do agree with Stiglitz on is the use of refundable tax credits to support real investment. Instead of this weird business about not taxing dividends and capital gains in the hope that maybe somehow this will support real investment, we actually give tax credits specifically to companies that build factories or hire more workers.

Stiglitz also does a good job of elucidating the concept of “corporate welfare”, officially called “tax expenditures”, in which subsidies for corporations are basically hidden in the tax code as rebates or deductions. This is actually what Obama was talking about when he said “spending in the tax code”, (he did not invent the concept of tax expenditures), but since he didn’t explain himself well even Jon Stewart accused him of Orwellian Newspeak. Economically a refundable tax rebate of $10,000 is exactly the same thing as a subsidy of $10,000. There are some practical and psychological differences, but there are no real economic differences. If you’re still confused about tax expenditures, the Center for American Progress has a good policy memo on the subject.

Stiglitz also has some changes to make to the personal income tax, all of which I think are spot-on. First we increase the marginal rates, particularly at the very top. Next we equalize rates on all forms of income, including capital income. Next, we remove most, if not all, of the deductions that allow people to avoid paying the rate it says on paper. Finally, we dramatically simplify the tax code so that the majority of people can file a simplified return which basically just says, “This is my income. This is the tax rate for that income. This is what I owe.” You wouldn’t have to worry about itemizing your student loans or mortgage payments or whatever else; just tally up your income and look up your rate. As he points out, this would save a lot of people a lot of stress and also remove a lot of economic distortions.

He talks about how we can phase out the mortgage-interest deduction in particular, because it’s clearly inefficient and regressive but it’s politically popular and dropping it suddenly could lead to another crisis in housing prices.

Stiglitz has a deorbit for anyone who thinks capital income should not be taxed:

“There is, moreover, no justification for taxing those who work hard to earn a living at a higher rate than those who derive their income from speculation.”

By equalizing rates on labor and capital income, he estimates we could raise an additional $130 billion per year—just shy of what it would take to end world hunger. (Actually some estimates say it would be more than enough, others that it would be about half what we need. It’s definitely in the ballpark, however.)

Stiglitz actually proposes making a full deduction of gross household income at $100,000, meaning that the vast majority of Americans would pay no income tax at all. This is where he begins to lose me, because it necessarily means we aren’t going to raise enough revenue by income taxes alone.

He proposes to make up the shortfall by introducing a value-added tax, a VAT. I have to admit a lot of countries have these (including most of Europe) and seem to do all right with them; but I never understood why they are so popular among economists. They are basically sales taxes, and it’s very hard to make any kind of sales tax meaningfully progressive. In fact, they are typically regressive, because rich people spend a smaller proportion of their income than poor people do. Unless we specifically want to disincentivize buying things (and a depression is not the time to do that!), I don’t see why we would want to switch to a sales tax.

At the end of the paper Stiglitz talks about the vital difference between short-term spending cuts and long-term fiscal sustainability:

“Thus, policies that promote output and employment today also contribute to future growth – particularly if they lead to more investment. Thus, austerity measures that take the form of cutbacks in spending on infrastructure, technology, or education not only weaken the economy today, but weaken it in the future, both directly (through the obvious impacts, for example, on the capital stock) but also indirectly, through the diminution in human capital that arises out of employment or educational experience. […] Mindless “deficit fetishism” is likely to be counterproductive. It will weaken the economy and prove counterproductive to raising revenues because the main reason that we are in our current fiscal position is the weak economy.”

It amazes me how many people fail to grasp this. No one would say that paying for college is fiscally irresponsible, because we know that all that student debt will be repaid by your increased productivity and income later on; yet somehow people still think that government subsidies for education are fiscally irresponsible. No one would say that it is a waste of money for a research lab to buy new equipment in order to have a better chance at making new discoveries, yet somehow people still think it is a waste of money for the government to fund research. The most legitimate form of this argument is “crowding-out”, the notion that the increased government spending will be matched by an equal or greater decrease in private spending; but the evidence shows that many public goods—like education, research, and infrastructure—are currently underfunded, and if there is any crowding-out, it is much smaller than the gain produced by the government investment. Crowding-out is theoretically possible but empirically rare.

Above all, now is not the time to fret about deficits. Now is the time to fret about unemployment. We need to get more people working; we need to create jobs for those who are already seeking them, better jobs for those who have them but want more, and opportunities for people who have given up searching for work to keep trying. To do that, we need spending, and we will probably need deficits. That’s all right; once the economy is restored to full capacity then we can adjust our spending to balance the budget (or we may not even need to, if we devise taxes correctly).

Of course, I fear that most of these policies will fall upon deaf ears; but Stiglitz calls us to action:

“We can reform our tax system in ways that will strengthen the economy today, address current economic and social problems, and strengthen our economy for the future. The economic agenda is clear. The question is, will the vested interests which have played such a large role in creating the current distorted system continue to prevail? Do we have the political will to create a tax system that is fair and serves the interests of all Americans?”

Why being a scientist means confronting your own ignorance

2015-10-212015-10-21 PNRJ core principles confirmation bias, falsification, ignorance, knowing, knowledge, Popper, science, stupidity, The Armor of Truth

I read an essay today arguing that scientists should be stupid. Or more precisely, ignorant. Or even more precisely, they should recognize their ignorance when all others ignore and turn away.

What does it feel like to be wrong?

It doesn’t feel like anything. Most people are wrong most of the time without realizing it. (Explained brilliantly in this TED talk.)

What does it feel like to be proven wrong, to find out you were confused or ignorant?

It hurts, a great deal. And most people flinch away from this. They would rather continue being wrong than experience the feeling of being proven wrong.

But being proven wrong is the only way to become less wrong. Being proven ignorant is the only way to truly attain knowledge.

I once heard someone characterize the scientific temperament as “being comfortable not knowing”. No, no, no! Just the opposite, in fact. The unscientific temperament is being comfortable not knowing, being fine with your infinite ignorance as long as you can go about your day. The scientific temperament is being so deeply uncomfortable not knowing that it overrides the discomfort everyone feels when their beliefs are proven wrong. It is to have a drive to actually know—not to think you know, not to feel as if you know, not to assume you know and never think about it, but to actually know—that is so strong it pushes you through all the pain and doubt and confusion of actually trying to find out.

An analogy I like to use is The Armor of Truth. Suppose you were presented with a piece of armor, The Armor of Truth, which is claimed to be indestructible. You will have the chance to wear this armor into battle; if it is indeed indestructible, you will be invincible and will surely prevail. But what if it isn’t? What if it has some weakness you aren’t aware of? Then it could fail and you could die.

How would you go about determining whether The Armor of Truth is really what it is claimed to be? Would you test it with things you expect it to survive? Would you brush it with feathers, pour glasses of water on it, poke it with your finger? Would you seek to confirm your belief in its indestructibility? (As confirmation bias would have you do?) No, you would test it with things you expect to destroy it; you’d hit it with everything you have. You’re fire machine guns at it, drop bombs on it, pour acid on it, place it in a nuclear testing site. You’d do everything you possibly could to falsify your belief in the armor’s indestructibility. And only when you failed, only after you had tried everything you could think of to destroy the armor and it remained undented and unscratched, would you begin to believe that it is truly indestructible. (Popper was exaggerating when he said all science is based on falsification; but he was not exaggerating very much.)

Science is The Armor of Truth, and we wear it into battle—but now the analogy begins to break down, for our beliefs are within us, they are part of us. We’d like to be able to point the machineguns at armor far away from us, but instead it is as if we are forced to wear the armor as the guns are fired. When a break in the armor is found and a bullet passes through—a belief we dearly held is proven false—it hurts us, and we wish we could find another way to test it. But we can’t; and if we fail to test it now, it will only endanger us later—confront a false belief with reality enough and it will eventually fail. A scientist is someone who accepts this and wears the armor bravely as the test guns blaze.

Being a scientist means confronting your own ignorance: Not accepting it, but also not ignoring it; confronting it. Facing it down. Conquering it. Destroying it.

What if employees were considered assets?

2015-10-142015-10-12 PNRJ core principles, public policy accounting, asset, capital, credit, debit, equity, labor, liability, nonzero-sum, Robert Reich, wealth, zero-sum

JDN 2457308 EDT 15:31

Robert Reich has an interesting proposal to change the way we think about labor and capital:
“First, are workers assets to be developed or are they costs to be cut?” “Employers treat replaceable workers as costs to be cut, not as assets to be developed.”

This ultimately comes down to a fundamental question of how our accounting rules work: Workers are not considered assets, but wages are considered liabilities.

I don’t want to bore you with the details of accounting (accounting is often thought of as similar to economics, but really it’s the opposite of economics: Whereas economics is empirical, interesting, and fundamentally nonzero-sum, accounting is arbitrary, tedious, and zero-sum by construction), but I think it’s worth discussing the difference between how capital and labor are accounted.

By construction, every credit must come with a debit, no matter how arbitrary this may seem.

We start with an equation:

Assets + Expenses = Equity + Liabilities + Income

When purchasing a piece of capital, you credit the equity account with the capital you just bought, increasing it, then debit the expense account, increasing it as well. Because the capital is valued at the price at which you bought it, the increase in equity exactly balances the increase in expenses, and your assets, liabilities, and income do not change.

But when hiring a worker, you still debit the expense account, but now you credit the liabilities account, increasing it as well. So instead of increasing your equity, which is a good thing, you increase your liabilities, which is a bad thing.

This is why corporate executives are always on the lookout for ways to “cut labor costs”; they conceive of wages as simply outgoing money that doesn’t do anything useful, and therefore something to cut in order to increase profits.

Reich is basically suggesting that we start treating workers as equity, the same as we do with capital; and then corporate executives would be thinking in terms of making a “capital gain” by investing in their workers to increase their “value”.

The problem with this scheme is that it would really only make sense if corporations owned their workers—and I think we all know why that is not a good idea. The reason capital can be counted in the equity account is that capital can be sold off as a source of income; you don’t need to think of yourself as making a sort of “capital gain”; you can make, you know, actual capital gains.

I think actually the deeper problem here is that there is something wrong with accounting in general.

By its very nature, accounting is zero-sum. At best, this allows an error-checking mechanism wherein we can see if the two sides of the equation balance. But at worst, it makes us forget the point of economics.

While an individual may buy a capital asset on speculation, hoping to sell it for a higher price later, that isn’t what capital is for. At an aggregate level, speculation and arbitrage cannot increase real wealth; all they can do is move it around.

The reason we want to have capital is that it makes things—that the value of goods produced by a machine can far exceed the cost to produce that machine. It is in this way that capital—and indeed capitalism—creates real wealth.

Likewise, that is why we use labor—to make things. Labor is worthwhile because—and insofar as—the cost of the effort is less than the benefit of the outcome. Whether you are a baker, an author, a neurosurgeon, or an auto worker, the reason your job is worth doing is that the harm to you from doing it is smaller than the benefit to others from having it done. Indeed, the market mechanism is supposed to be structured so that by transferring wealth to you (i.e., paying you money), we make it so that both you and the people who buy your services are better off.

But accounting methods as we know them make no allowance for this; no matter what you do, the figures always balance. If you end up with more, someone else ends up with less. Since a worker is better off with a wage than they were before, we infer that a corporation must be worse off because it paid that wage. Since a corporation makes a profit selling a good, we infer that a consumer must be worse off because they paid for that purchase. We track the price of everything and understand the value of nothing.

There are two ways of pricing a capital asset: The cost to make it, or the value you get from it. Those two prices are only equal if markets are perfectly efficient, and even then they are only equal at the margin—the last factory built is worth what it can make, but every other factory built before that is worth more. It is that difference which creates real wealth—so assuming that they are the same basically defeats the purpose.

I don’t think we can do away with accounting; we need some way to keep track of where money goes, and we want that system to have built-in mechanisms to reduce rates of error and fraud. Double-entry bookkeeping certainly doesn’t make error and fraud disappear, but it at least does provide some protection against them, which we would lose if we removed the requirement that accounts must balance.

But somehow we need to restructure our metrics so that they give some sense of what economics is really about—not moving around a fixed amount of wealth, but making more wealth. Accounting for employees as assets wouldn’t solve that problem—but it might be a start, I guess?

The scissors of supply and demand

2015-10-032015-10-03 PNRJ core principles, public policy business cycle, conservative, demand, demand-side, immortality, liberal, Marshall, policy, Say's Law, supply, supply-side, unemployment

JDN 2457299 EDT 17:03

In recent posts I talked about demand and then I talked about supply. Now it’s time to talk about both at once–which is where the real magic happens. Alfred Marshall famously compared supply and demand to the lower and upper blades of a pair of scissors:

We might as reasonably dispute whether it is the upper or the under blade of a pair of scissors that cuts a piece of paper, as whether value is governed by utility or cost of production. It is true that when one blade is held still, and the cutting is effected by moving the other, we may say with careless brevity that the cutting is done by the second; but the statement is not strictly accurate, and is to be excused only so long as it claims to be merely a popular and not a strictly scientific account of what happens.

~Alfred Marshall, Principles of Economics

Before Marshall, it was actually rather common to debate whether prices are determined by supply or by demand. Actually there seems to be a certain branch of Marxists today who insist upon the “labor theory of value” that seems to rest upon a similar sort of confusion, basically saying that the real value of something is entirely determined by its cost of supply. If the value of something were strictly determined by the labor put into making it, there would be literally no reason to ever make anything. If the value you get from a good is precisely equal to the labor put into it, there is no net benefit to ever making any goods. At most, embodying labor in a product might allow you to transfer labor from one person to another; but there would be no such thing as real economic growth. In order to have real economic growth, products must end up being worth more than what it cost to make them—that is, their value of demand must exceed their cost of supply.

Toward the other end of the political spectrum, we have “Say’s Law”, which says that “supply creates its own demand”; that is, that there is never any such thing as too much or too little overall demand in an economy, because supplying a good automatically makes that good available to trade for something else. I hate to even call it a “law” because isn’t even like the Pirate Code; it’s not even useful as a guideline, it’s just flat wrong. There is absolutely no reason that making something would make someone else want to buy it from you. You can make all sorts of things that nobody wants to buy; the possibilities are endless, really. Balls of lint dusted with powdered sugar, broken ballpoint pens dipped in motor oil, burnt-out lightbulbs covered in melted Swiss cheese. It’s possible that someone might want to buy such bizarre items (call them “postmodernist found art” or something), but there clearly isn’t a large market for such goods, even if you should decide to manufacture thousands of them. Even in an aggregate sense, there’s also no particular reason to think that we can’t have an economy where millions of products pile up on shelves because no one can afford to buy them; indeed, that’s basically what happens in a recession.

In fact, the converse, “demand creates its own supply”, is considerably closer to true. It’s still not strictly true—centuries of searching for the elixir of immortality have failed to produce it, though modern genetic engineering just might finally succeed where all else has failed. (After all, every new technology is impossible… until it isn’t.) But in the long run, this converse law (it doesn’t have a name so far as I know) does contain an important grain of truth: If people want something badly enough, they will spend enormous resources in order to find a way to get it. If you know that a lot of people want something that no one is supplying, it behooves you to find a way to provide it—it might just make you a billionaire. Over centuries of technological advancement, humanity has found ways to provide many goods and services that were previously thought impossible, and one of the central benefits of a capitalist economy is that it provides powerful economic incentives for entrepreneurs to innovate and find ways to provide goods that people have always wanted but never had. Yet, even so, it isn’t true that demand creates its own supply—certainly not in the short run.

Neither supply or demand on its own does much of anything. You can have insatiable demand for something nobody can supply (the aforementioned elixir of immortality), and it still won’t be sold. You can have endless supply of something nobody demands (vacuum?), and it will remain worthless. It’s only when you have both supply and demand that a market becomes possible.

One of the central insights of modern economics is that prices and quantities in a capitalist market are determined simultaneously by supply and demand. In general, both supply and demand are constantly changing in response to events in the world, and thus the prices and quantities of goods shift from one equilibrium to another. In order to predict exactly how they will shift, we would need to know how both supply and demand have changed.

As Marshall alludes to in the above quotation, in some cases we can take either supply or demand as fixed and then the other one is what matters; but these are only special cases. In general, both supply and demand are subject to the winds of changing markets, and we need to keep track of both at once. If that sounds really difficult, that’s because it is—most of what economists do in the real world ultimately amounts to finding ways to distinguish supply effects from demand effects in various situations. Even most statistical methods in econometrics were basically designed as means of separating out demand-related causes from supply-related causes.

A lot of policy questions ultimately depend upon whether supply or demand is the dominant factor: If the business cycle is primarily driven by changes in demand, it makes sense to use monetary and fiscal policy to stabilize the economy (short version: it is, and it does). If it were instead driven by supply (“supply-side economics”), it would instead be better to make structural changes that reduce costs of production. (Why is this obviously wrong? Because there weren’t sudden increases in production costs in 2008—but there was a sudden collapse of consumer buying power. Maybe the 1973 recession can be explained by a sudden increase in oil prices, but there was no such supply shock in 2008.) If the labor market is primarily driven by demand, we need to find ways to get business to hire more people; but if it’s primarily driven by supply, we need to find ways to get people to get off their butts and try to find work. (Again, I think it’s pretty obvious that the former is true, not the latter—since at least 2000 there have never been as many job openings in the US as there were unemployed people.)

In the above policy questions the liberal view is the demand-side and the conservative view is the supply-side, but that need not be the case. Regarding renewable energy, for example, the more liberal view is that lots of people would want to buy electric cars and solar panels, if they were made available, but they aren’t—we are supply-constrained. The more conservative view is that the reason they aren’t selling more is that nobody particularly wants them and trying to force them on us is a fool’s errand—we are demand-constrained. Likewise when it comes to banking, liberals generally think that the reason there isn’t more credit is that banks refuse to supply loans, while conservatives (particularly from the banks themselves) usually argue that it’s because people aren’t willing to take the risk of taking out more loans.

The point, however, is that a lot of policy debates ultimately hinge upon the question of whether demand or supply is more important in driving a particular market—and since sometimes they are both important, sometimes the policy solution requires a combination of different approaches. One of the advantages of quantitative economic analysis is that we can determine exactly how much the costs and benefits of each policy option will be, and thereby choose the one that is most cost-effective.

In this way, “supply or demand?” is a lot like “nature or nurture?”; the answer is always “both”, but there are times when one factor or the other is more important for the policy question at hand.

How (not) to talk about the defense budget

2015-09-30 PNRJ core principles, public policy budget, CIA, college, defense, education, Facebook, healthcare, Lee Camp, Medicare, meme, military, SIPRI, Social Security, spending, UNDP

JDN 2457927 EDT 20:20.

This week on Facebook I ran into a couple of memes about the defense budget that I thought were worth addressing. While the core message that the United States spends too much on the military is sound, these particular memes are so massively misleading that I think it would be irresponsible to let them go unanswered.

First of all, this graph is outdated; it appears to be from about five years ago. If you use nominal figures for just direct military spending, the budget has been cut from just under $700 billion (what this figure looks like) in 2010 to only about $600 billion today. If you include verterans’ benefits, again nominally, we haven’t been below $700 billion since 2007; today we are now above $800 billion. I think the most meaningful measure is actually military spending as percent of GDP, on which we’ve cut military spending from its peak of 4.7% of GDP in 2010 to 3.5% of GDP today.

It’s also a terrible way to draw a graph; using images instead of bars may be visually appealing, but it undermines the most important aspect of a bar graph, which is that you can easily visually compare relative magnitudes.

But the most important reason why this graph is misleading is that it uses only the so-called “discretionary budget”, which includes almost all military spending but only a small fraction of spending on healthcare and social services. This creates a wildly inflated sense of how much we spend on the military relatively to other priorities.

In particular, we’re excluding Medicare and Social Security, which are on the “mandatory budget”; each of these alone is comparable to total military spending. Here’s a very nice table of all US government spending broken down by category.

Let’s just look at federal spending for now. Including veterans’ benefits, we currently spend $814 billion per year on defense. On Social Security, we spend $959 billion. On healthcare, we spend $1,018 billion per year, of which $536 billion is Medicare.

We also spend $376 billion on social welfare programs and unemployment, along with $149 billion on education, $229 billion servicing the national debt, and $214 billion on everything else (such as police, transportation, and administration).

I’ve made you a graph that accurately reflects these relative quantities:

As you can see, the military is one of our major budget items, but the largest categories are actually pensions (i.e. Social Security) and healthcare (i.e. Medicare and Medicaid).

Given the right year and properly adjusted bars on the graph, the meme may strictly be accurate about the discretionary budget, but it gives an extremely distorted sense of our overall government spending.

The next meme is even worse:

Again the figures aren’t strictly wrong if you use the right year, but we’re only looking at the federal discretionary budget. Since basically all military spending is federal and discretionary, but most education spending is mandatory and done at the state and local level, this is an even more misleading picture.

Total annual US military spending (including veteran benefits) is about $815 billion.
Total US education spending (at all levels) is about $922 billion.

Here’s an accurate graph of total US government spending at all levels:

That is, we spend more on education than we do on the military, and dramatically more on healthcare.

However, the United States clearly does spend far too much on the military and probably too little on education; the proper comparison to make is to other countries.

Most other First World Countries spend dramatically more on education than they do on the military.

France, for example, spends about $160 billion per year on education, but only about $53 billion per year on the military—and France is actually a relatively militaristic country, with the 6th-highest total military spending in the world.

Germany spends about $172 billion per year on education, but only about about $44 billion on the military.

In absolute figures, the United States overwhelms all other countries in the world—we spend as much as at least the next 10 combined.

Using figures from the Stockholm International Peace Research Institute (SIPRI), the US spends $610 billion of the world’s total $1,776 billion, meaning that over a third of the world’s military spending is by the United States.

This is a graph of the top 15 largest military budgets in the world.

One of these things is not like the other ones…

It probably makes the most sense to compare military spending as a portion of GDP, which makes the US no longer an outlier worldwide, but still very high by First World standards:

If we do want to compare military spending to other forms of spending, I think we should do that in international perspective as well. Here is a graph of education spending versus military spending as a portion of GDP, in several First World countries (military from SIPRI and the CIA, and education from the UNDP):

Our education spending is about average (though somehow we do it so inefficiently that we don’t provide college for free, unlike Germany, France, Finland, Sweden, or Norway), but our military spending is by far the highest.

How about a meme about that?

	Wonderful news from… on What is the cost of all t…
	Wonderful news from… on What does nonviolence mea…
	PNRJ on What would a world without pov…
	butterr44 on What would a world without pov…
	What would a world w… on The housing affordability cris…

Human Economics

Cognitive development economics: Understanding the mind in order to feed the world

core principles