Oct 7 JDN 2458399

It’s been a little while since I’ve done a really straightforward economic post. It feels good to get back to that.

You are no doubt familiar with the “Manufacturer’s Suggested Retail Price” or MSRP. It can be found on everything from books to dishwashers to video games.

The MSRP is a very simple concept: The manufacturer suggests that all retailers sell it (at least the initial run) at precisely this price.

Why would they want to do that? There is basically only one possible reason: They are trying to sustain tacit collusion.

The game theory of this is rather subtle: It requires that both manufacturers and retailers engage in long-term relationships with one another, and can pick and choose who to work with based on the history of past behavior. Both of these conditions hold in most real-world situations—indeed, the fact that they don’t hold very well in the agriculture industry is probably why we don’t see MSRP on produce.

If pricing were decided by random matching with no long-term relationships or past history, MSRP would be useless. Each firm would have little choice but to set their own optimal price, probably just slightly over their own marginal cost. Even if the manufacturer suggested an MSRP, retailers would promptly and thoroughly ignore it.

This is because the one-shot Bertrand pricing game has a unique Nash equilibrium, at pricing just above marginal cost. The basic argument is as follows: If I price cheaper than you, I can claim the whole market. As long as it’s profitable for me to do that, I will. The only time it’s not profitable for me to undercut you in this way is if we are both charging just slightly above marginal cost—so that is what we shall do, in Nash equilibrium. Human beings don’t always play according to the Nash equilibrium, but for-profit corporations do so quite consistently. Humans have limited attention and moral values; corporations have accounting departments and a fanatical devotion to the One True Profit.

But the iterated Bertrand pricing game is quite different. If instead of making only one pricing decision, we make many pricing decisions over time, always with a high probability of encountering the same buyers and sellers again in the future, then I may not want to undercut your price, for fear of triggering a price war that will hurt both of our firms.

Much like how the Iterated Prisoner’s Dilemma can sustain cooperation in Nash equilibrium while the one-shot Prisoner’s Dilemma cannot, the iterated Bertrand game can sustain collusion as a Nash equilibrium.

There is in fact a vast number of possible equilibria in the iterated Bertrand game. If prices were infinitely divisible, there would be an infinite number of equilibria. In reality, there are hundreds or thousands of equilibria, depending on how finely divisible the price may be.

This makes the iterated Bertrand game a coordination game—there are many possible equilibria, and our task is to figure out which one to coordinate on.

If we had perfect information, we could deduce what the monopoly price would be, and then all choose the monopoly price; this would be what we call “payoff dominant”, and it’s often what people actually try to choose in real-world coordination games.

But in reality, the monopoly price is a subtle and complicated thing, and might not even be the same between different retailers. So if we each try to compute a monopoly price, we may end up with different results, and then we could trigger a price war and end up driving all of our profits down. If only there were some way to communicate with one another, and say what price we all want to set?

Ah, but there is: The MSRP. Most other forms of price communication are illegal: We certainly couldn’t send each other emails and say “Let’s all charge $59.99, okay?” (When banks tried to do that with the LIBOR, it was the largest white-collar crime in history.) But for some reason economists (particularly, I note, the supposed “free market” believers of the University of Chicago) have convinced antitrust courts that MSRP is somehow different. Yet it’s obviously hardly different at all: You’ve just made the communication one-way from manufacturers to retailers, which makes it a little less reliable, but otherwise exactly the same thing.

There are all sorts of subtler arguments about how MSRP is justifiable, but as far as I can tell they all fall flat. If you’re worried about retailers not promoting your product enough, enter into a contract requiring them to promote. Proposing a suggested price is clearly nothing but an attempt to coordinate tacit—frankly not even that tacit—collusion.

MSRP also probably serves another, equally suspect, function, which is to manipulate consumers using the anchoring heuristic: If the MSRP is $59.99, then when it does go on sale for $49.99 you feel like you are getting a good deal; whereas, if it had just been priced at $49.99 to begin with, you might still have felt that it was too expensive. I see no reason why this sort of crass manipulation of consumers should be protected under the law either, especially when it would be so easy to avoid.

There are all sorts of ways for firms to tacitly collude with one another, and we may not be able to regulate them all. But the MSRP is literally printed on the box. It’s so utterly blatant that we could very easily make it illegal with hardly any effort at all. The fact that we allow such overt price communication makes a mockery of our antitrust law.