Michael Bacharach and the wrong question in economics
Let’s imagine two people who have to choose, separately and without being able to speak to each other, between two options: High and Low. If both choose High, each earns 10 euros. If both choose Low, they each earn 5. If they choose different options, neither of them earns anything. What should they do? The answer seems almost too easy. It’s better to choose ‘High’. Ten euros is better than five and, above all, it’s better for both of them. But let’s try to explain why it is rational to choose ‘High’. If I think the other person will choose ‘High’, it is in my best interests to choose ‘High’ too. But if, for some reason, I think the other person will choose ‘Low’, then it is also in my best interests to choose ‘Low’. My rational choice depends on what I believe the other person will do. But the other person’s choice also depends on what they think I will do. I can then ask myself what they think I think they will do, and carry on like this without ever reaching the conclusion that seemed obvious from the start. Why on earth would two rational people agree on five euros when they could have ten?
It is the game that the Oxford economist Michael Bacharach called Hi-Lo. On the face of it, it is one of the simplest games imaginable. For Bacharach, however, it becomes a very rigorous test of rational choice theory. There are two equilibria: High-High and Low-Low. The former is clearly better than the latter for both players, yet standard theory, reasoning in terms of best individual responses, fails to provide sufficient reasons to prefer it. We can certainly think that if we expect the other player to choose High, it is better to choose High. But from this conditional proposition we cannot derive the unconditional conclusion that it is always better to choose High. It is precisely this difficulty that Bacharach regarded as one of the fundamental problems of game theory.
This point is particularly interesting because there is no conflict of interest here. Nobody has to be selfless. Nobody has to give anything up so that the other person can be better off. Nor is there a problem of distributive fairness: High-High allocates more to both than Low-Low. If the theory struggles to explain High’s choice, therefore, we cannot get away with introducing social preferences, aversion to inequality or reciprocity. The problem lies elsewhere. And it is here that Bacharach begins to challenge a much deeper assumption underlying economic theory. Who is it that chooses?
Before choosing
To attempt to answer this question about the identity of the decision-maker, however, we need to take a step back. Before turning his attention to this topic, Bacharach had worked extensively on another classic problem in game theory: that of the so-called focal points, a concept introduced into economics by Nobel laureate Thomas Schelling. How do two people coordinate, Schelling wondered, when there are many possible solutions and they cannot communicate with one another? In a famous experiment, Schelling asked people where they would go in New York to meet, without having had the chance to agree in advance on a place and time. In principle, there are thousands of possible combinations. Yet most people indicated Grand Central Station at 12 noon. Among all the possible solutions, Schelling observes, some ‘stand out’. They become focal points. This is where standard theory encounters a problem. If two alternatives are identical in terms of the outcomes they produce, there should be no rational reason to choose one over the other. In real life, however, people constantly make use of characteristics that the model considers irrelevant: a famous place, a round number, a particular shape, a colour that stands out from the rest.
Bacharach takes this anomaly very seriously and develops a theory, the Variable Frame Theory, to explain how it works. The underlying idea is simple, but it has profound consequences. An individual never makes a choice whilst observing the world from a completely neutral point of view. Some features of the situation enter their mental representation, whilst others do not. The frame is precisely the set of variables through which the subject conceptualises the problem. Suppose, for example, that we see a series of letters and have to choose one. The same physical action – circling the letter U – can be represented as ‘choosing the U’, ‘choosing a vowel’ or ‘choosing the letter that is different from the others’. The action is the same, but the object of the choice changes depending on the description under which it is considered.


