The policy-ineffectiveness proposition (PIP) is a
new classical theory proposed in 1975 by
Thomas J. Sargent
Thomas John Sargent (born July 19, 1943) is an American economist and the W.R. Berkley Professor of Economics and Business at New York University. He specializes in the fields of macroeconomics, monetary economics, and time series econometric ...
and
Neil Wallace
Neil Wallace (born 1939) is an American economist and professor of economics at Penn State University. He is considered one of the main proponents of new classical macroeconomics in the field of economics.
Education
Wallace earned his BA in e ...
based upon the theory of
rational expectations
In economics, "rational expectations" are model-consistent expectations, in that agents inside the model are assumed to "know the model" and on average take the model's predictions as valid. Rational expectations ensure internal consistency in ...
, which posits that monetary policy cannot systematically manage the levels of output and employment in the economy.
Theory
Prior to the work of Sargent and Wallace, macroeconomic models were largely based on the
adaptive expectations
In economics, adaptive expectations is a hypothesized process by which people form their expectations about what will happen in the future based on what has happened in the past. For example, if people want to create an expectation of the inflatio ...
assumption. Many economists found this unsatisfactory since it assumes that agents may repeatedly make systematic errors and can only revise their expectations in a backward-looking way. Under adaptive expectations, agents do not revise their expectations even if the government announces a policy that involves increasing money supply beyond its expected growth level. Revisions would only be made after the increase in the money supply has occurred, and even then agents would react only gradually. In each period that agents found their expectations of inflation to be wrong, a certain proportion of agents' forecasting error would be incorporated into their initial expectations. Therefore, equilibrium in the economy would only be converged upon and never reached. The government would be able to maintain employment above its natural level and easily manipulate the economy.
This behavior by agents is contrary to that which is assumed by much of economics. Economics has firm foundations in assumption of rationality, so the systematic errors made by agents in macroeconomic theory were considered unsatisfactory by Sargent and Wallace. More importantly, this behavior seemed inconsistent with the
stagflation of the 1970s
In economics, stagflation or recession-inflation is a situation in which the inflation rate is high or increasing, the economic growth rate slows, and unemployment remains steadily high. It presents a dilemma for economic policy, since actions ...
, when high inflation coincided with high unemployment, and attempts by policymakers to actively manage the economy in a Keynesian manner were largely counterproductive. When applying
rational expectations
In economics, "rational expectations" are model-consistent expectations, in that agents inside the model are assumed to "know the model" and on average take the model's predictions as valid. Rational expectations ensure internal consistency in ...
within a macroeconomic framework, Sargent and Wallace produced the policy-ineffectiveness proposition, according to which the government could not successfully intervene in the economy if attempting to manipulate output. If the government employed monetary expansion in order to increase output, agents would foresee the effects, and wage and price expectations would be revised upwards accordingly. Real wages would remain constant and therefore so would output; no
money illusion
In economics, money illusion, or price illusion, is a cognitive bias where money is thought of in nominal, rather than real terms. In other words, the face value (nominal value) of money is mistaken for its purchasing power (real value) at a previ ...
occurs. Only
stochastic shocks to the economy can cause deviations in employment from its natural level.
Taken at face value, the theory appeared to be a major blow to a substantial proportion of macroeconomics, particularly
Keynesian economics
Keynesian economics ( ; sometimes Keynesianism, named after British economist John Maynard Keynes) are the various macroeconomic theories and models of how aggregate demand (total spending in the economy) strongly influences economic output ...
. However, criticisms of the theory were quick to follow its publication.
Criticisms
The Sargent and Wallace model has been criticised by a wide range of economists. Some, like
Milton Friedman
Milton Friedman (; July 31, 1912 – November 16, 2006) was an American economist and statistician who received the 1976 Nobel Memorial Prize in Economic Sciences for his research on consumption analysis, monetary history and theory and the ...
, have questioned the validity of the rational expectations assumption.
Sanford Grossman
Sanford "Sandy" Jay Grossman (born July 21, 1953) is an American economist and hedge fund manager specializing in quantitative finance. Grossman’s research has spanned the analysis of information in securities markets, corporate structure, prop ...
and
Joseph Stiglitz
Joseph Eugene Stiglitz (; born February 9, 1943) is an American New Keynesian economist, a public policy analyst, and a full professor at Columbia University. He is a recipient of the Nobel Memorial Prize in Economic Sciences (2001) and th ...
argued that even if agents had the cognitive ability to form rational expectations, they would be unable to profit from the resultant information since their actions would then reveal their information to others. Therefore, agents would not expend the effort or money required to become informed and government policy would remain effective.
The
New Keynesian economists
Stanley Fischer
Stanley Fischer ( he, סטנלי פישר; born October 15, 1943) is an Israeli American economist who served as the 20th Vice Chair of the Federal Reserve from 2014 to 2017. Fisher previously served as the 8th governor of the Bank of Israel ...
(1977) and
Edmund Phelps
Edmund Strother Phelps (born July 26, 1933) is an American economist and the recipient of the 2006 Nobel Memorial Prize in Economic Sciences.
Early in his career, he became known for his research at Yale's Cowles Foundation in the first half of ...
and
John B. Taylor (1977) assumed that workers sign nominal wage contracts that last for more than one period, making wages "sticky". With this assumption the model shows government policy is fully effective since, although workers rationally expect the outcome of a change in policy, they are unable to respond to it as they are locked into expectations formed when they signed their wage contract. Not only is it possible for government policy to be used effectively, but its use is also desirable. The government is able to respond to stochastic shocks in the economy which agents are unable to react to, and so stabilise output and employment.
The
Barro–Gordon model showed how the ability of government to manipulate output would lead to
inflationary bias. The government would be able to cheat agents and force unemployment below its natural level but would not wish to do so. The role of government would therefore be limited to output stabilisation.
Since it was possible to incorporate the rational expectations hypothesis into macroeconomic models whilst avoiding the stark conclusions that Sargent and Wallace reached, the policy-ineffectiveness proposition has had less of a lasting impact on macroeconomic reality than first may have been expected. In fact, Sargent himself admitted that macroeconomic policy could have nontrivial effects, even under the rational expectations assumption, in the preface to the 1987 edition of his textbook ''Dynamic Macroeconomic Theory'':
:'The first edition appeared at a time when discussions of the 'policy-ineffectiveness proposition' occupied much of the attention of macroeconomists. As work of
John B. Taylor has made clear, the methodological and computational implications of the hypothesis of rational expectations for the theory of optimal macroeconomic policy far transcend the question of whether we accept or reject particular models embodying particular
neutrality
Neutral or neutrality may refer to:
Mathematics and natural science Biology
* Neutral organisms, in ecology, those that obey the unified neutral theory of biodiversity
Chemistry and physics
* Neutralization (chemistry), a chemical reaction ...
propositions... The current edition contains many more examples of models in which a government faces a nontrivial policy choice than did the earlier edition.'
Despite the criticisms,
Anatole Kaletsky has described Sargent and Wallace's proposition as a significant contributor to the
displacement of Keynesianism
The post-war displacement of Keynesianism was a series of events which from mostly unobserved beginnings in the late 1940s, had by the early 1980s led to the replacement of Keynesian economics as the leading theoretical influence on economic life ...
from its role as the leading economic theory guiding the governments of advanced nations.
Reception
While the policy-ineffectiveness proposition has been debated, its validity can be defended on methodological grounds. To do so, one has to realize its conditional character. For new , countercyclical stimulation of aggregate demand through monetary policy instruments is neither possible nor beneficial ''if the assumptions of the theory hold''. ''If'' expectations are rational and ''if'' markets are characterized by completely flexible nominal quantities and ''if'' shocks are unforeseeable white noises, then macroeconomic systems can deviate from the equilibrium level only under contingencies (i.e. random shocks). However, no systematic countercyclical monetary policy can be built on these conditions, since even monetary policy makers cannot foresee these shocks hitting economies, so no planned response is possible. According to the common and traditional judgement,
new classical macroeconomics
New classical macroeconomics, sometimes simply called new classical economics, is a school of thought in macroeconomics that builds its analysis entirely on a neoclassical framework. Specifically, it emphasizes the importance of rigorous foundat ...
brought the inefficiency of economic policy into the limelight. Moreover, these statements are always undermined by the fact that new classical assumptions are too far from life-world conditions to plausibly underlie the theorems. So, it has to be realized that the precise design of the assumptions underlying the policy-ineffectiveness proposition makes the most influential, though highly ignored and misunderstood, scientific development of
new classical macroeconomics
New classical macroeconomics, sometimes simply called new classical economics, is a school of thought in macroeconomics that builds its analysis entirely on a neoclassical framework. Specifically, it emphasizes the importance of rigorous foundat ...
. New did not assert simply that activist economic policy (in a narrow sense: monetary policy) is ineffective.
Robert Lucas and his followers drew the attention to ''the conditions under which this inefficiency probably emerges''.
See also
*
Neutrality of money
Neutral or neutrality may refer to:
Mathematics and natural science Biology
* Neutral organisms, in ecology, those that obey the unified neutral theory of biodiversity
Chemistry and physics
* Neutralization (chemistry), a chemical reaction ...
*
Sticky wages and prices
Related theories
*
Ricardian equivalence
*
Say's law
In classical economics, Say's law, or the law of markets, is the claim that the production of a product creates demand for another product by providing something of value which can be exchanged for that other product. So, production is the source ...
*
Treasury view
References
Further reading
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*{{Cite book , last=Sargent , first=Thomas , year=1987 , title=Dynamic Macroeconomic Theory , edition=2nd , publisher=Academic Press , isbn=978-0-12-619751-8 , url-access=registration , url=https://archive.org/details/macroeconomicthe00sarg
Macroeconomic theories
Macroeconomic policy
New classical macroeconomics