A theory of economic policy

New paper by Thomas Palley tilted "A theory of economic policy lock-in and lock-out via hysteresis: rethinking economists’ approach to economic policy" has been published. From the abstract:

This paper uses hysteresis to develop the concept of policy lock-in and lock-out. Policy changes may near-irrevocably change the economy’s structure, thereby changing the distribution of wealth, income and power. That may lock-in policy by changing the political equilibrium. Exit costs that block policy reversals also cause lock-in. Conventional thinking treats policy as a dial which is adjusted according to the economy’s state. Policy lock-in questions the dial formulation and raises new issues for optimal policy design. It also offers insights into economic and political crisis theory. Policy lock-in is illustrated with examples that include tax policy, government spending, the euro, globalization, and the neoliberal policy experiment.

Read full paper here.

A Theory of Economic Policy Lock-in and Lock-out via Hysterisis

Locked out

By Thomas Palley

This paper explores lock-in and lock-out via economic policy. It argues policy decisions may near-irrevocably change the economy’s structure, thereby changing its performance. That causes changed economic outcomes concerning distribution of wealth, income and power, which in turn induces locked-in changes in political outcomes. That is a different way of thinking about policy compared to conventional macroeconomic stabilization theory. The latter treats policy as a dial which is dialed up or down, depending on the economy’s state. Lock-in policy is illustrated by the euro, globalization, and the neoliberal policy experiment.

Read paper here.

Hysteresis and the natural rate

I've been teaching on the price and quantity interactions, and the natural rate or NAIRU (Non Accelerating Inflation Rate of Unemployment), that is the level of activity at which you have price stability. One of the papers assigned is the one by Franklin Serrano (here or here for a Spanish version; another assigned paper is this one by yours truly). By the way, I've dealt with the issue of hysteresis briefly before here, mostly to distinguish it from path dependency, following Setterfield (Serrano also suggests differences between heterodox and more conventional views on hysteresis).

As noted by Serrano, the research by Nelson and Plosser (1982) (here; subscription required) and Real Business Cycle (RBC) authors suggests that GDP follows a random walk, and as a result after a productivity shock (which they measure as changes in TFP, in spite of significant problems with that measure; see here) output does not return to its previous trend. The point is that once the output trend is affected there are persistent effects that change the trend itself, that is hysteresis. Fluctuations are variations of the optimal level itself.

Serrano correctly points out that "this means that the long run trend of output is not only partially determined by whatever drives short run output (presumably aggregate demand) but rather that potential output is actually fully determined by the trend of whatever drives actual output. As it is well known, this result of strong hysteresis in the output (GDP) series has been taken to provide evidence in favor of the 'real business cycles' strand of new classical macroeconomics in which the common element driving trend and cycle are factor supplies and their productivity." The natural rate or NAIRU is supply determined, but is variable (something that, in a different context, Robert Gordon would call the Time Varying NAIRU or TV-NAIRU).

Supply shocks imply that in a boom the potential output moves first, and actual output adjusts as individuals readjust to higher productivity. Hence, the output gap, if defined as the difference between actual and potential output, becomes negative. And if you believe in a Phillips curve and some sort of central bank monetary rule, a negative output gap suggests a deflationary pressure (and yes RBC authors do believe in endogenous money). Yes, that's what the RBC theory implies! In fact, according to Kydland and Prescott (1990): "the price level has displayed a clear countercyclical pattern."*

Serrano points out a simpler (Occam's Razor applies) explanation for the favorable evidence on hysteresis, namely that demand (in fact, the autonomous components of demand) determine potential output (the supermultiplier). Note that this approach does not require, as the RBC or the acceleracionist versions of the Phillips Curve, any definite relationship between prices and quantities. As noted here (and here) before, there is no reason to expect an unambiguous or systematic relation between prices and quantities, unless you think that prices are always driven by excess (or lack of) demand.

As Serrano argues the: "trend and the cycle indeed have a common nature as the empirical literature shows but this common nature reflects that both are explained by demand (not supply) factors" and "with full hysteresis in output levels and partial inertia on inflation, 'demand-pull' inflation is just a temporary phenomenon and therefore does not determine 'core' or persistent inflation." And it is hard not to agree on this with New Keynesians, and their dismissal of supply shocks as the main cause of business cycles. It is harder to agree with their insistence on a natural rate, even if it's variable.

* The obvious historical event they would have in mind is the stagflation of the 1970s. Note, however, that more often than not deflationary periods are contractionary, like the 1930s. Of course the oil shocks and the increase in costs can explain, together with wage resistance and price inertia, the inflationary pressures of the 1970s in a model that is perfectly compatible with demand driven recessions.

New heterodox blog

A New Blog (in Spanish) Crisol Econométrico (something like A Melting Pot of Econometrics; traduttore, traditore!) for those interested in quantitative and heterodox analyses of economic policy in Latin America. Last entry on hysterisis, which we dealt also here, and unit roots.

Path Dependency and Hysteresis

I promised to discuss the difference between these two concepts a while ago. The idea of path dependency is related to Joan Robinson’s famous objection according to which equilibrium is not an actual outcome of real economic processes, and it is for that reason an inadequate tool for analyzing accumulation.  Her view would suggest that path dependency should be seen as a property of models that break with conventional methodological stances, and, in particular, with the dominant neoclassical school.

It is important to note that mainstream defenders of the idea that ‘history matters’, like Paul David (of QWERTY fame), tend to disagree with the view that path dependency implies a rupture with neoclassical economics. David (2001, p. 22) says, in this regard: “imagine … my utter surprise to find this approach being attacked as a rival paradigm of economic analysis, whose only relevance consisted in the degree to which it could be held to represent a direct rejection of the normative, laissez-faire message of neoclassical economics!”  For David, path dependency is a property of dynamic and stochastic processes and cannot be used to assert anything about models and propositions derived in static and deterministic setting [which is, apparently, what he thinks neoclassical economics is all about].

Mark Setterfield's research might hold the key to this issue, by differentiating hysteresis [a concept from physics, that shows that mainstream economists do have physics envy!] and path dependency, and suggesting that the former, more typical of mainstream models, is a special case of the latter, more general and the concept often linked to heterodox models. He suggests that hysteresis is a variation of traditional equilibrium analysis, which implies that some displacements from equilibrium would be self-correcting while others would not. Hysteresis results from the non-uniqueness of equilibrium and under certain conditions the economic system would adjust to a new equilibrium. On the other hand, Setterfield argues that the typical path dependent model is based on cumulative causation, a concept that harks back to Gunnar Myrdal and Nicholas Kaldor’s contributions to economics. In this case, transitory shocks always have permanent effects.

A simple example might illustrate the difference between the more restricted notion of hysteresis and cumulative causation. In the conventional mainstream description of labor markets, an increase in unemployment insurance that allows workers to hold out longer for better paid jobs increases the natural rate of unemployment. After a fall in demand (an external shock), if structural changes to the labor market like higher benefits take place, the level of unemployment will increase and eventually fall, as real wages fall, but to the new and higher natural rate [think of Gordon's Time Varying NAIRU]. Hysteresis implies that history matters, but the system is still self-adjusting.

The quintessential example of cumulative causation is associated to the Kaldor-Verdoorn Law, which says that output growth leads to rising labor productivity. Thus, higher demand leads to higher output growth, which implies higher productivity, lower costs, and higher income in a virtuous circle of expansion. There are several possible expansion paths, depending on the strength of the multiplier-accelerator forces and the Kaldor-Verdoorn coefficient, rather than a single equilibrium to which the system adjusts. There is no adjustment to an optimal equilibrium level, no natural rate fixed or varying. The heterodox notion demands the rejection of the natural rate.