Showing posts with label Marshall. Show all posts
Showing posts with label Marshall. Show all posts

Saturday, August 19, 2017

A theory of economic policy and the role of institutions

Nicola Acocella published a paper in the Journal of Economic Surveys (a free, preliminary version is available here) on the development of the theory of economic policy. Acocella is clearly fully aware of the differences between classical political economics and marginalism (neoclassical economics).* And he dismisses the pre-margnialist views on economic policy as being unsystematic and devoid of general principles.
In his words:
Most classical writers and the marginalists had suggested cases where public intervention was in order. This had been so for Smith (1776), Ricardo (1817), Mill (1848), Marshall (1890), Walras (1874-1877, 1898). But these cases were mainly what Walras called ‘examples of empirical policy’ rather than consistent policy. They were certainly dictated on the basis of an analytical evaluation of the circumstances suggesting them, but were not part of a systematic and consistent assessment of the foundations and the articulation of public policy.
In his view, economic policy as an autonomous discipline, meaning one based on theoretical principles, only started with Sidgwick,  Marshall and Pigou, that is, with Welfare Economics or Social Choice Theory, which apparently now is referred to as Implementation Theory (I didn't know that, I might confess). So it is in the debate of the 1930s, with Robbins and his followers and critics, and more fundamentally with Arrow's Impossibility Theorem that he sees the development of the main themes of a theory of economic policy.

He also suggests that before the development of a the theory of economic policy proper "the ‘night-watchman’ position became an exception as most classical and marginalist economists tended to state a number of specific or general cases where government intervention was in order." I'm not fully convinced about that. Sure there were some views about government intervention, but for the most part the Victorian consensus, among economists (not necessarily in practice, meaning actual economic policy) was for free trade, adherence to the rules of the Gold Standard, and sound finance. The idea of the minimal state was probably dominant, and the exceptions, particularly among marginalists that dominated in the UK at least, were associated to market failures.

The two major obstacles to this dominant view that government action was possible, in Acoccela's view were due to Arrow and Lucas. In his words, these 'vital failures' were: "the impossibility of taking people’s preferences as a reference for public action, underlined by Arrow (1951) and ‘radical’ objections to effectiveness of public action of the kind raised by Lucas (1976)." I should note that it seems that, in his view, the major critiques have been successfully dealt with, by Sen and his followers in one field and New Keynesians in the other, and the current consensus would be that government action is possible and desirable.

In this view, then, the history of the development of of the field is one in which the profession goes from being in favor of government action up to the development of the theory (essentially the from the beginning of marginalism to the 40s), broadly speaking, to being critical from the 50s to the 80s, with a slow return to a more interventionist consensus ever since. And maybe this describes well the field of Implementation Theory. But it strikes me as being at odds with conventional views of what the profession thinks about the role of government over time.

I mean, normally you would think of the profession as being essentially for laissez-faire, the reason why sometimes there is a conflation of classical and marginalist authors, and then after the Great Depression and the Keynesian Revolution (even if not complete, and dominated by an imperfectionist view) there would be an interventionist turn, which starts to be contested in the 1970s, with the Conservative Revolution and the Great Inflation. The apotheosis of the return of the market would come with the fall of the Soviet Union, shock therapy and the so-called Washington Consensus. The question would be to what extent this neoliberal dominance has been undermined by the last Global Financial Crisis (I would say less than what people think).

I also think that the dismissal of the classical political economy approach to economic policy, which was based on historical understanding of the specific conditions of a particular situation, is a mistake, and that there is a lot be learned from that tradition. Note that for classical political economy authors history and institutions, and, hence, policy analysis, were at a different level of abstraction, and had a different relation with the core of the theory (value and distribution). At any rate, this is an interesting paper worth reading.

* For example, he is careful to note that the meaning of the invisible hand in Adam Smith is often out of context. However, he argues that: "we use the term ‘invisible hand’ as a metaphor of the Smithian position as well as of later theories, in particular neo-classical thinking, which has then prevailed, even if the latter are deprived of some social aspects of the working of the market that certainly were in Adam Smith." This reading of Smith leaves room for intervention in the case of imperfections, and seems to follow the ideas of Acoccela's mentor, the famous Italian economist Federico Caffè.

Friday, September 26, 2014

History versus equilibrium: a false dichotomy

The title comes from Joan Robinson's famous essay. However, the motivation is to clarify some comments on a previous post on what Keynes meant by unemployment equilibrium (sent to me, but not published). There is a relatively widespread notion among some post-Keynesians that neoclassical economics assumes always a single unique equilibrium, and that Keynes, or at least his closer followers like Robinson, believed in multiple equilibria. The idea is that post-Keynesians believe in an unstable, uncertain capitalist system in which full employment is only one possibility.

Beyond what one may think about equilibrium, there is no basis in the history of economic ideas for that view. Keynes was a Marshallian, and as such did believe in the notion of a single stable long run equilibrium of the system. The radical element in Keynes analysis is that such equilibrium might be suboptimal, that is, one in which resources are not fully utilized. He is very clear when he says in the General Theory that:
"it is an outstanding characteristic of the economic system in which we live that, whilst it is subject to severe fluctuations in respect of output and employment, it is not violently unstable. Indeed it seems capable of remaining in a chronic condition of sub-normal activity for a considerable period without any marked tendency either towards recovery or towards complete collapse. Moreover, the evidence indicates that full, or even approximately full, employment is of rare and short-lived occurrence. Fluctuations may start briskly but seem to wear themselves out before they have proceeded to great extremes, and an intermediate situation which is neither desperate nor satisfactory is our normal lot."
So what Keynes said is pretty clear, fluctuations around a normal equilibrium. Unemployment is the normal position, the long run equilibrium around which the system fluctuates. Like the old classical political economists (e.g. Smith, Ricardo, and Marx) and the marginalists of his time (e.g. Pigou, and Marshall) Keynes believed in a single stable long run equilibrium position. Note that nothing in Keynes analysis implies that the long run equilibrium is ever attained, or that it cannot be affected by the process by which it is approached, and, hence that it would be path-dependent [the supermultiplier story with a Kaldor-Verdoorn process is path dependent and is still a long run equilibrium position].

The problems associated to the negative impact of uncertainty, and failed expectations, and the institutions and conventions that are relevant in a certain historical context to minimize the effects of instability are all part of the normal operation of the economy for Keynes, and not, like in neoclassical models, superimposed on an essentially stable system. In other words, Keynes equilibrium theory is not a-historical, and hence does not require the addition of more realistic (historical?) elements to provide explanation of say why the system is stuck below full employment equilibrium.

For example, lack of demand (caused by stagnant wages and not enough fiscal stimulus) means that the US economy will the near future fluctuate around levels of unemployment that are above the previous normal levels. In the graph below (source) that is visible in a trend that was lower in the 1950s and 1960s, and goes up in the 1970s and 1980s, only to go down (as a result of a series of bubbles) in the 1990s, and, as I suggested, is likely to go up again. This trend represents the normal position to which Keynes alluded in the passage cited above. Unemployment fluctuates, but is not violently unstable (sometimes it might be; asks the Greeks). In the neoclassical model, in contrast, without imperfections, be that price rigidities or lack of information or any other kind, the system would move to full employment. That's why they often resort to change what the meaning of full employment is (the natural rate goes up; nudge, nudge; wink wink).
However, the interesting thing is that while the old neoclassical authors shared the classical political economists and Keynes notion of a stable long run equilibrium (optimal for the neoclassical, and not so for Keynes and the classical authors), they have departed from that view after the capital debates. In fact, it is in the Walrasian world of Arrow-Debreu's intertemporal equilibrium, that the notion of multiple equilibria becomes relevant (for the reasons why the mainstream changed their views on equilibrium go here; Garegnani classic paper titled "On a Change in the Notion of Equilibrium in Recent Work on Value" is the source of this idea). But in that world, anything could happen, it is wildly unstable and there no forces bringing the economy back to its normal position. Certainly not what Keynes thought, and also not an accurate description of the graph above.

More importantly, the very idea of long run equilibrium is central to our ability to theorize about the functioning of real, historically and institutionally specific economies. It is the fact that there are persistent forces, with regularities, which allows to say something meaningful about the functioning of the economy. If uncertainty rendered economic calculation impossible, then even Keynes' theory about how effective (autonomous) demand determines income, would be irrelevant, and in that case post-Keynesians would have (notice I said would have, since I don't think this is the right way to describe post-Keynesian economics) more in common with the modern neoclassical economists that have embraced multiple equilibria and all sorts of imperfections.

Sunday, May 5, 2013

In the long run we are NOT all dead

Niall Ferguson has apologized for his offensive suggestion that Keynes' phrase on being dead in the long run was somehow related to his sexuality or the fact that he was childless (more here and here). Good for him. Note, however, that in that famous phrase from the Tract on Monetary Reform, from 1923, Keynes was still very much a conventional Marshallian author who thought that full employment would reassert itself, and that the Quantity Theory of Money (QTM) worked pretty well. In fact, it is often said that the Tract was Milton Friedman's favorite among all of Keynes' books.

The full quote says:
"But this long run is a misleading guide to current affairs. In the long run we are all dead. Economists set themselves too easy, too useless a task if in tempestuous seasons they can only tell us that when the storm is long past the ocean is flat again."
The point of the quote is that in the long run everything would be fine, since markets do get to full employment, and so, even without intervention, deflation and inflation do its magic, but the process is too long and painful, so it would be more reasonable to act in the short run. This was typical of the Cambridge version of Marginalism, which was very much in favor of government intervention to deal with market imperfections in the short run. This is true of Marshal and Pigou, as well as Robertson, and certainly Keynes, before the General Theory. Note that this does not mean, as most people think, that one should only be concerned with the short run. The point is that action in the short run facilitates the road towards the fully adjusted equilibrium in the long run.

This was still essentially Keynes' view by 1930, when he published the Treatise on Money, a book that is at heart Wicksellian [so at least he got rid of the QTM in this book], and that suggests that unemployment results from a monetary rate of interest that is too high with respect to the natural rate, in practice as a result from the Gold Standard rules, which Keynes wanted to abandon. [This precedes the modern views that the Gold Standard caused the Depression, by the way, as say defended by Barry Eichengreen]. This was a cyclical crisis that could be solved by reducing the monetary rate of interest, and in the short run employment programs, something Keynes defended in Can Lloyd George Do It?

The point of the General Theory (GT) is that there is no natural rate of interest, meaning that reducing the rate of interest would not bring investment to the full employment level of savings, and that the crisis was caused by lack of demand. The equilibrium between investment and savings was determined by variations in the level of output, and in the long run we are not self adjusted to full employment. Hence, the very logic of the phrase above is debunked by Keynes, when he became Keynesian, so to speak, and got rid of the old modes of thinking. Intervention is not needed because in the long run we are dead, but because the long run depends on the short run, and we tend to fluctuate around a sub-optimal position.

So in the long run we are NOT dead in the GT, in the absence of counter-cyclical policies we are all in deep trouble. Keynes was very much concerned about the possibility of capitalism to promote well being for all in the long run. In other words, not only is Ferguson wrong about the effects of Keynes' sexuality and lack of children on his economic reasoning, but he does not even get the point of the phrase.

PS: The best book to understand the theoretical changes in Keynes' views is still Edward Amadeo's  Keynes' Principle of Effective Demand, his PhD dissertation, supervised by Murray Milgate, and co-supervised by Lance Taylor, published with an intro by Vicky Chick.

Thursday, March 14, 2013

Sraffa and the Marshallian system

(Sraffa circa 1976)

G. L. S. Shackle argues in The Years of High Theory that ‘there began in the mid-1920s an immense creative spasm, lasting for fourteen years until the Second World War, and yielding six or seven major innovations of theory, which together have completely altered the orientation and character of economics’ (Shackle, 1967, p. 5). However, by 1967, the two most important developments of this period—Keynes’s principle of effective demand and Sraffa’s criticism of the marginalist theory of value—were rapidly fading from the main corpus of mainstream theory.

The relative ease with which neoclassical economics reasserted its main conclusions is, in fact, explained by Shackle’s account of those years. First, Sraffa’s critique of the Marshallian theory of value is seen only as a step in the development of the theories of imperfect competition by Joan Robinson and Edward Chamberlin. Second, Keynes’s General Theory is seen as stating that unemployment results from the existence of uncertainty and irrational expectations (Shackle, 1967, p. 129). Both developments can be interpreted as asserting that market imperfections render neoclassical theory, although internally coherent, irrelevant for the analysis of the real world.

Also Shackle’s failure in 1967 — well after the publication of Production of Commodities — to acknowledge the importance of the revival of classical political economy to the debates of the 1930s represents a serious inadequacy of his interpretation of ‘the years of high theory’.

Before getting into Sraffa's critique of Marshall, it is worth noticing that Sraffa came to economics via monetary economics, like Ricardo and Keynes. His dissertation for the Law Degree, L’Inflazione Monetaria in Italia Durante e Dopo la Guerra (subscription required), dealt with postwar inflation and the return to the Gold Standard, the same topic of Keynes’s Tract on Monetary Reform. According to Eatwell and Panico (subscription required), in the analysis of the asymmetric effects of inflation and deflation Sraffa reveals the heterodox character of his position, more akin with the works of the classical authors and Marx than the conventional marginalist analysis. The notion that social conflicts and monetary factors determine the normal real wage was part of Sraffa’s analysis, although several elements of his analysis were still conventional, e.g. the acceptance of the Quantity Theory and of the Purchasing Power Parity theory.

Sraffa’s criticism of the Marshallian theory of supply represents an analogous situation, in the sense that some elements of the conventional marginalist views were still present. Marshall’s or Sraffa’s dilemma (which appears in Sraffa's 1926 paper) refers to the incompatibility between increasing returns and perfect competition. It is a long period problem. Sraffa’s critique can be summarized in the following way. First, rising costs derive from diminishing returns to substitution, and, therefore, in the general case where there are no fixed factors, increasing costs do not seem to exist. Secondly, increasing returns are incompatible with perfect competition. In the long period, when the firm cannot experience marginal costs arising from the existence of some fixed input, there can be no diminishing returns. Replication is always possible, except for the case of indivisibilities. In addition, Sraffa showed that increasing returns to scale are inconsistent with the notion of perfect competition.

In the case of increasing returns, the average cost is decreasing, implying that the marginal cost is below average variable cost, and, hence, there is no infinite, non-zero solution for the profit maximization problem. In other words, there is a tendency for the firm to expand to infinite size. Sraffa’s argument proves the failure of perfectly competitive assumptions to determine any equilibrium of the individual firm. Two alternatives are opened by Sraffa’s critique of Marshallian theory. If it is not legitimate to treat average cost as either increasing or decreasing within the framework of perfect competition, we are left with the result that the only satisfactory assumption is that of constant returns. On the other hand, ‘everyday experience shows that a very large number of undertakings work under conditions of individual diminishing costs’ (Sraffa, 1926, p. 543), which suggests that we should instead abandon the notion of perfect competition.

Sraffa considered the imperfect competition approach to be the only logical way to develop the theory of value along Marshallian lines. However, he showed no inclination to pursue this solution, and he appears to have already been working toward the revival of the classical approach. The origins of this project can be traced back to his early draft of the opening propositions of the Production of Commodities, which he asked Keynes to read in 1928 (Sraffa, 1960, p. vi). The reasons for not pursuing imperfect competition were never quite explained by Sraffa, but are fairly reasonable to infer (note that in Cambridge it was two of his students, Richard Kahn and Joan Robinson, that developed the imperfect competition theory).

Note that in order to obtain partial equilibrium, which is what the Marshallian model presumes, one must assume that prices in a particular industry are not affected by and do not affect the prices in other industries. Hence, externalities have to be internal to the industry, since otherwise production in one sector would affect the prices in other industries [perfect competition in partial equilibrium, the U-shaped cost curves and the equilibrium at the minimum with marginal cost equal marginal revenue, require also that externalities are external to the firm, since if they weren't the firm would became a monopolist; of course externalities that are internal to an industry and external to firms are an empty set]. That seems to be a dead end. Sraffa was already interested in the determination of long term prices. By this time, the summer of 1927 when he was preparing his ‘Lectures on Advanced Value Theory’ that he gave from 1928 until 1930, it was already clear to him that he needed to start from classical preocupation of determining relative prices and one of the distributive variables (the rate of profits or wages) strictly in material terms, that is, the quantities of labor and commodities needed to produce commodities.

For further on Sraffa's critique of Marshall see Gary Mongiovi's paper here (subscription required). For a general critique of Shackle's stance in the history of 'the years of high theory' read this one. For the implications of Sraffa's 1960 book for economics go to this old post (yes on the capital debates!).

Monday, September 17, 2012

Nick Rowe's misconceptions about Sraffians I

Nick Rowe continues his very welcome discussion of the issues related to the capital debates in a recent post (see also the reply by Unlearning Economics). However, there are several misconceptions in his post that are worth clarifying. I'm going to deal with his first four assumptions (1 and 2 in this post, and 3 and 4 in a subsequent one), which are the more substantial from a theoretical point of view, namely:
1. Some economists in Cambridge UK wanted to explain prices without talking about preferences. I don't know why they didn't want to talk about preferences;

2. They made some special assumptions that helped them explain prices from technology alone, without talking about preferences. Like: all labour is identical; all technology is linear; prices never change over time;

3. But they still couldn't explain the rate of interest. Because it's hard to explain the rate of interest if you don't want to talk about time preferences. And all the other prices depend on the rate of interest, as well as on technology. So they assumed the rate of interest was exogenous;

4. Some economists in Cambridge US made a very special assumption that let them explain the rate of interest without talking about time preferences. They assumed that there was only one good, and it could be converted back and forth between the consumption good and the capital good by waving a wand.

The Cambridge economists are, of course, Sraffa and his followers. First, one of the most frequent confusions about Sraffa was that he assumed that demand, and, as a result, preferences were irrelevant. Before I tackle the issue per se, it is worth quoting this phrase, brought to my attention in Robert Vienneau’s blog:
"I am sorry to have kept your MS so long - and with so little result. The fact is that your opening sentence is for me an obstacle which I am unable to get over. You write: 'It is a basic proposition of the Sraffa theory that prices are determined exclusively by the physical requirements of production and the social wage-profit division with consumers demand playing a purely passive role.' Never have I said this: certainly not in the two places to which you refer in your note 2. Nothing, in my view, could be more suicidal than to make such a statement. You are asking me to put my head on the block so that the first fool who comes along can cut it off neatly. Whatever you do, please do not represent me as saying such a thing." -- Piero Sraffa (1964). Letter to Arun Bose (italics added).
Clearly Sraffa says that demand plays a role. However, the role is not the same as in marginalist theory. One has to understand what role demand played in the surplus approach in the determination of relative prices to get what Sraffa is saying.

Classical authors, in particular Adam Smith and David Ricardo (and certainly not Marx), did not think in terms of individual utility. When they talk about utility they are referring to social utility. Hence, commodities to be produced must be socially useful, otherwise they would not be produced, since nobody would buy them, but their price, their exchange value, is not based or connected with their use value. For example, Smith in his discussion of the diamond/water paradox (Wealth of Nations, Book I, ch. IV) argues that things with a high use value often have little or no exchange value, since things that are not costly to produce will command no price, even if they are useful. It is only with Thomas De Quincey, after Ricardo and the demise of classical economics, that the notion that utility (and use value) had a functional relation to exchange value becomes entrenched in economics, an idea that was picked up by Stuart Mill, and through him by Marshall (marginalism or neoclassical economics), as it is well documented by Krishna Bharadwaj (subscription required).

As Bharadwaj says of the Quincey/Mill/Marshall notion:

"This was a different notion of use-value than that accepted by Smith and Ricardo, for whom use-value was a necessary condition for a commodity to possess in order to be an object of exchange, but referred to the physical properties socially known to belong to a commodity, and not dependent upon the individual's estimation of its capacity to gratify subjective inclinations, measured in quantitative terms. In fact, use-value and exchange-value were incomparable in so far as the former covered the qualitative aspect and the latter was a quantitative notion. In De Quincey and Mill, the two notions had become quantitatively comparable (one acting as an extreme limit upon another) and this was only a step towards the later resolution of the paradox in terms of 'total' and 'marginal' utility."
In other words, social utility not individual estimation is behind the classical notion of preferences. The point then is that social utility and, as a result, demand considerations are essential for the determination of long term prices. However, these preferences are not the subjective preferences of individuals, about which nothing scientific can be said, since there are no regularities and they can change for irrational and circumstantial reasons.

The utility that society attaches to a particular good, say a car, however, can be taken as given at a particular point in time. The reasons are not only directly connected to objective characteristics, like the fact that a car is a means of transportation or negatively that they worsen environmental conditions, but also that cars socially may be a source of status, as Veblen later suggested. In other words, preferences (and demand) are socially determined and taken as given for the determination of relative prices, but there is a role for historical and institutional analysis in understanding why and how demand and preferences change over time. The idea was, also, that social preferences are relatively slow to change, and for that reason one can take them as given.

Thus, in the surplus approach there is a role for historical/institutional analysis (not just social preferences, but income distribution too, e.g. the discussion of the determination of the exogenous real wage), and a different role for theoretical analysis (the determination of exchange value). Note that the assumption of given social preferences, as correctly noted by Unlearning Economics, can be seen as a ceteris paribus clause. So Nick is right that there is no reason not to talk about preferences. However, it is far from clear that knowledge has been advanced by the marginalist treatment of individual subjective preferences. As I noted in my comments to his post, the reasons for convex, homothetic preferences is not dictated by knowledge about a regularity about people’s behavior, but simply by the teleological need of finding a solution to the maximization problem. I would say rather that there is no reason to talk about individual preferences. Social utility is fine.

Point 2 is just a poorly built straw man of the Sraffian/surplus approach model. There is no assumption of a linear technology. In fact, that’s typical of the neoclassical aggregative models. The only situation in which a linear relation between wages and profits in the Sraffian model is in the case of the standard commodity [I still owe you all a post on that topic; didn't forget], if this is what Nick means by linearity, which would be the only relevant case (unless he is against input-output models). The input-output framework of any system in which production is done by using commodities to produce commodities (a feature of the real world, by the way), does not imply that there is no technical change either. Technical input-output coefficients can change.

Note that any theory has to say something about the determination of relative prices for a given technology anyway. By the way, in this case Sraffa assumes, like the classical authors, a given level of output (again is a ceteris paribus condition, and a different theory of the determination of output is needed; we know through Garegnani, Sraffa’s disciple, that effective demand is what Sraffa had in mind, and not some version of Say’s Law). That does not imply, hence, constant returns to scale, since that would require an increase in output proportional to the increase in inputs, something that cannot happen when output is given. Remember that output is given for the theory of long term prices only.

Finally, there is enough literature showing that one can reduce, theoretically speaking, labor of different qualities to a uniform type. It is ironic that a neoclassical author would complain about this, since the production function, which is beset with unfathomable problems, also assumes identical labor, and in fact it also assumes a unique capital good (not many means of production) and is fundamentally a world of only one commodity (on this and point 4 by Nick, more on the following post).

TO BE CONTINUED