Posts Tagged Dani Rodrik

Is Economics A Gun That Only Fires Left?

Sometimes it seems like economist’s pet principles are applied selectively, in such a way that they attack ideas generally endorsed by the left end of the political spectrum. This isn’t to say economists themselves are ideologically inclined toward any opinion; merely, that key aspects of their own framework, and the way they present these aspects, lends itself to a more ‘right-friendly’ way of thinking.

In part, the issue is merely one of a disparity between how economists present issues to the public and how they speak to others in academia. Dani Rodrik noted this issue in his book The Globalisation Paradox. Here he describes a situation where a reporter asks an economist whether free trade is beneficial:

We can be fairly certain about the kind of response [the reporter] will get: “Oh yes, free trade is a great idea,” the economist will immediately say, possibly adding: “And those who are opposed to it either do not understand the principle of comparative advantage, or they represent the selfish interests of certain lobbies (such as labor unions).”

Rodrik then contrasts this with how such a question would be answered in the classroom:

Let [the student] pose the same question to the instructor: Is free trade good? I doubt that the question will be answered as quickly and succinctly this time around. The professor is in fact likely to be stymied and confused by the question. “What do you mean by ‘good’?” she may ask. “Good for whom?… As we will see later in this course, in most of our models free trade makes some groups better off and others worse off… But under certain conditions, and assuming we can tax the beneficiaries and compensate the losers, freer trade has the potential to increase everyone’s well-being…”

This adherence to basic, market-friendly principles over nuance can be found often in ‘pop’ economics: for example, economist Paul Krugman does it in his book Peddling Prosperity. The book is intended as an survey of nonsensical ideas from both the left and the right, remedying them both with a cold hard dose of facts, plus some basic economics. However, Krugman treats the left and right somewhat asymmetrically: with the right, he primarily opts for facts, whereas with the left, he uses economic principles

This is quite possibly because the right’s arguments, though they are taken to an extreme, have economic principles on their side, while the left’s do not. The ‘supply side’ economics that Krugman takes issue with is really just an extreme statement of the well known principle of deadweight loss, which suggests that taxes decrease output. If taxes reduce output by enough, then it logically follows that not only output, but overall revenues might fall if we raise taxes. Krugman would not question the principle, so he spends several chapters documenting evidence against the idea*.

Krugman then follows this up with a section berating the ‘strategic traders’, endorsed by Bill Clinton and others on the centre-left. Strategic trade suggested a role for government policy in promoting industry, because various clustering effects, economies of scale and positive feedback loops could mean that the initial wave of government investment could kick start an industry. As Krugman himself notes, such dynamic effects and ‘historical path dependence’ could render comparative advantage obsolete, since comparative advantage posits a more fundamental, innate reason a country produces a particular good, one that cannot be changed with policy (one that may be more applicable to agriculture).

Yet, in contrast with his section aimed at refuting the right, Krugman offers scant evidence suggesting government intervention doesn’t work. Instead, he effectively restates the theory of comparative advantage, coupled with a typical story to illustrate it. This is despite explicitly suggesting it might not be applicable in the previous chapter. When pushed, Krugman is prepared to fall back on his pro-market principles, even in areas where he knows they may not apply.

William Easterly does something similar in his book The Elusive Quest for Growth. The book is a survey of various policies than have purported to be panaceas for development, such as education, investment and population control. (As you can see, economists really love writing their “I’m an economist, here’s how it is” manifestos). Easterly finds every supposed development panacea wanting based on the available evidence, which is fine. However, occasionally he supplements his arguments with an excruciating example of ‘economic logic’ that always looks out of place.

For example, in the section on increasing availability of condoms, Easterly essentially makes the argument ‘how could people be lacking condoms? If they were, the free market would provide them!’ I am reminded of the joke about the economist who does not pick up a £10 note from the ground, because, if it were really there, somebody would already have picked it up. Easterly is a smart guy with a lot of concern for the poor, and I have a hard time believing he wouldn’t agree that a country might lack the institutions to deliver condoms, that people might lack the education to know why they’d need them, that it might conflict with their beliefs, etc. But the ease with which he can apply a pet economic principle is just too tempting, so he ignores these factors.

Another example is where Easterly asserts that population growth cannot be a problem, because “an additional person is a potential profit opportunity for a person that hires him or her” and as a result “the real wage will adjust until the demand for workers equals the supply.” It’s quite clear things don’t function this smoothly in labour markets even in developed countries; for theoretical reasons as to why, Easterly need look no further than John Maynard Keynes; failing that, modern work on labour market frictions might prove sufficient. Again we see a neat but overly simplistic principle applied when even the economist themselves surely knows better.

So it is not uncommon for economists to prefer their more ‘free market’ principles over nuance when writing for a popular audience**. But is this problem only limited to popular economics? Economists seem to think so; to them, the issue is primarily one of communication, and knowing the limits of your models. This is fine as it goes. However, there are reasons to believe this bias extends into the murky depths of academia.

In my opinion, there is one major culprit of selective application in economics, and it is one that cannot be explained by economists simplifying their work for public consumption: the Lucas Critique. The Lucas Critique suggests that adjusting policy based on observed empirical relationships from the past will alter the conditions under which these observations were generated, hence rendering the relationship obsolete.

Unfortunately, in practice, Lucas’ version of the critique seems to have been used to beat ‘Keynesians’ over the head, rather than being universally applied as a tool to further understanding. To illustrate this, here are some areas I think Lucas critique-style thinking could be applied, but hasn’t:

  • Milton Friedman’s methodology. If a ‘black box’ theory corroborates well with past evidence but we aren’t entirely sure the internal mechanics are accurate, there’s no reason to believe the corroboration will hold, or to know how the mechanics of the system will change, if we change policy.
  • Nominal GDP Targeting (NGDPT). This hasn’t caught on much on the left (in my opinion, for primarily ideological reasons: it’s anti-Keynesian, it partly absolves the private sector of responsibility for recessions). But it doesn’t seem to have occurred to proponents of NGDPT that we must ask if the relationship between inflation, RGDP and NGDP will break down if we try to exploit it for policy purposes. This is despite the fact that we are talking about precisely the same variables as  the Phillips Curve, the primary theory to which the Lucas Critique was initially applied.
  • The supposed “deep parameters” of human behaviour on which Lucas suggests we construct economic models, such as technology and preferences. For a neoclassical economist, you are born with a set of preferences and you die with them, while in many models technology is a vaguely defined exogenous parameter. Yet a single example can show that both of these things can change with policy: government investment, which is at the root of a large number of technological break throughs. These break throughs have often resulted in new products, creating preferences that otherwise wouldn’t have existed. A model with fixed, exogenous parameters for technology and preferences is therefore hugely fallible to policy changes.

The fact that the critique hasn’t been applied to these examples leads me to believe it’s often only used to preserve existing economic theory.  In fact, the critique itself is really just a narrow version of the more general principle of reflexivity, noted by many before. Reflexivity is an ever-present problem that suggests an evolving relationship between policy and theory, not a principle that means we can fall back on economist’s preferred methods.

Is the Lucas Critique the only culprit? Well, I’ve found economists are generally critical of the assumptions and mechanics of heterodox models, despite appealing to Friedmanite arguments when questioned about their own. I’ve also found economists (okay, one) appeal to how businessmen really behave when defending their theories despite not paying much credence to alternative theories based on the same principle, such as cost-plus pricing. So maybe economists need to air out their theories and principles a bit, rather than simply applying them where it suits them.

Economist’s simple stories often capture some truths, which is why they will defend them to the death. But too often this becomes a matter of protecting a core set of beliefs, and being unwilling to apply them in new ways or even abandon them altogether. So economists end up deferring to their framework when it isn’t appropriate, or only interpreting it in their preferred way, particularly when they communicate their ideas to the public. The result can be that misleading conclusions about the economy remain prominent, even when economist’s own frameworks, interpreted completely, don’t necessarily imply them. Perhaps if economists were more willing to open up their theories, which can sometimes feel like something of a black box, these misinterpretations would be exposed.

*I won’t delve into the evidence here because it’s not the point, but you can easily find Krugman making the same arguments on his blog if you’re curious.

**In fairness to Krugman and Easterly, these books were written a while ago, and I’m sure they have updated their positions since then. I only wish to show that economists use this tactic, not that any one economist endorses any particular position.

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