Spectrum of Macroeconomic Thought Marx Radical Political Economy Kalecki Post- Keynesian Keynes Keynesian (hydraulic Keynesians) Monetarist Friedman New Keynesian - New Monetarist(?) Lucas New Classical Austrian Sticky Wages/Prices Uncertainty Disequilibrium Markets Clear In Long-run Markets Clear in Short-Run Rat-X micro foundations Policy Ineffectiveness Policy Works

New Classicals in Their Own Words Lucas critique: …modern macroeconomic models are of no value in guiding policy … For purposes of conditional forecasting (what will happen conditional on some action), one needs to know the structural parameters. (But) a change in policy necessarily alters some parameters (for example, those describing the past behavior of the policy variables themselves. … expectations about future prices, tax rates, and income levels play a critical role in many demand and supply schedules in those (macroeconometric) models. [I]nvestment demand typically is supposed to respond to businessmen’s expectations of future tax credits, tax rates, and factor costs. The supply of labor, …, to the rate of inflation workers expect in the future. Such structural equations are usually identified by the assumption that the expectation about the factor price or rate of inflation is a function only of a few lagged values of the variable itself…However, the macro models themselves contain complicated dynamic interactions among endogenous variables, including factor prices and the rate of inflation. The casual treatment of expectations is not a peripheral problem in these models, for the role of expectations is pervasive and exerts a massive influence on their dynamic properties (a point Keynes himself insisted on). “The Failure of Keynesian Economics”

Equilibrium Business Cycle Theory Perhaps the most important failure of the classical model (was) its inability to explain the positive correlation between prices and/or wages and aggregate output or employment …contrary to the classical “neutrality” propositions. Policy ineffectiveness hypothesis: A distinguishing feature of the equilibrium macroeconometric models is that predicatable changes in the money supply do not affect real GNP or total employment. The new classical models continue to assume that markets always clear and that agents optimizeThe new classical models continue to assume that markets always clear and that agents optimize. A New Classical Story: Because they do not have all the information that would enable them to compute perfectly the relative prices they care about, agents make errors…[A]gents temporarily mistake a general increase in all absolute prices as an increase in the relative price of the good they are selling, leading them to increase their supply of that good…Since everyone is, on average, making the same mistake, aggregate output will rise… While such a theory predicts positive correlations between the inflation rate or money supply and the level of output, it also asserts that those correlations do not depict “tradeoffs” that can be exploited by a policy authority…There is no way the monetary authority can follow a systematic activist policy and achieve a rate of output (above the “natural” rate).