Microfoundations for stochastic frontiers

The purpose of the paper is to propose microfoundations for stochastic frontier models. Previous work shows that a simple Bayesian learning model supports gamma distributions for technical inefficiency in stochastic frontier models. The conclusion depends on how the problem is formulated and what assumptions are made about the sampling process and the prior. After the new formulation of the problem it turns out that the distribution of the one-sided error component does not belong to a known family. Moreover, we find that without specifying a utility function or even the cost inefficiency function, the relative effectiveness of managerial input can be determined using only cost data and estimates of the returns to scale. The point of this construction is that features of the inefficiency function u(z) can be recovered from the data, based on the solid microfoundation of expected utility of profit maximization but the model does not make a prediction about the distribution

New classical/real business cycle macroeconomics. The anatomy of a revolution

The aim of the present paper is to assess the new classical/real business cycle revolution, which dethroned Keynesian macroeconomics. In its first part, I critically discuss the microfoundations requirement that constitutes a cornerstone of the new approach and suggest an alternative, softer, formulation of it. The conclusion of this discussion is that the new classical/real business cycle revolution marked a transition from a soft to a demanding understanding of the microfoundations requirement. In the second part of the paper, I present additional salient traits of the new classical and the real business cycle stages of the revolution. While each of these stages brought a specific contribution to the revolution, I emphasize the decisive role played by Kydland and Prescott in re-orienting the type of work in which macroeconomists were engaged. Finally, in part three, I ponder upon the causes of this revolution. After presenting and assessing Prescott’s and Lucas’s accounts of the factors which gave rise to the new approach, I venture into muddier waters by raising the question of whether a political agenda underpinned the NC/RBC revolution.

Toward a new paradigm in open economy modeling: where do we stand?

This paper provides a selective, up-to-date survey of the recent, fast-growing literature on new open economy macroeconomics. Lucio Sarno begins with a review of the seminal paper in this literature, describing the baseline model proposed therein. He then covers a number of variants and generalizations of the baseline model involving the allowance for nominal rigidities, pricing to market, alternative preference specifications, and alternative financial markets structures. The author also discusses the recent stochastic extensions of these models, especially focusing on their implications for the link between risk and exchange rates and on new directions for the relevant literature.Econometric models ; Macroeconomics

Dynamic models with non clearing markets

Abstract This article studies a new class of models which synthesize the two traditions of general equilibrium with nonclearing markets and imperfect competition on the one hand, and dynamic stochastic general equilibrium (DSGE) models on the other hand. This line of models has become a central paradigm of modern macroeconomics for at least three reasons: (a) it displays solid microeconomic foundations, (b) it is a highly synthetic theory, which combines in a unified framework general equilibrium, nonclearing markets, imperfect competition, growth theory and rational expectations, (c) it is also an empirical success, leading to substantial progress towards matching real world statistics.dynamic stochastic models ; general equilibrium ; non clearing markets ; imperfect competition

EFFICIENT POLICY RULEFOR INFLATION TARGETING INCOLOMBIA

In a small macroeconomic model of the Colombian economy I investigate the problem of selecting an efficient simple policy rule - rules that exploit a reduced information set-that is consistent with inflation targeting. Even though simple policy rules are not as efficient as the optimal state-contingent policy rules, in the literature it has been shown that some simple rules can approximate them very well. I spell out the characteristics of the feedback and output parameters in simple Taylor and Inflation-forecast rules, as well as the optimal forecasting horizon for inflation targeting. Using stochastic simulations of the model it is found that, as expected, simple rules that use forecasts of inflation rather than just contemporaneous inflation have better stabilization properties.Inflation targeting, horizon, optimal policy rules, simple feedback rules,

A New Class of Production Functions and an Argument Against Purely Labor-Augmenting Technical Change

This paper follows Jones (2005) in his approach to deriving the global production function from microfoundations. His framework is generalized by allowing for dependence between the Pareto distributions of labor- and capital-augmenting developments. Using the Clayton copula family to capture this dependence, we derive a “Clayton-Pareto” class of production functions that nests both the Cobb-Douglas and the CES. Embedding the resultant production function in a neoclassical growth framework, we draw conclusions for the long-run direction of technical change. Jones’ result of Cobb-Douglas global production functions and purely labor-augmenting technical change hinges on the assumption of independence of marginal Pareto distributions. In our more general case, the shape of local production functions matters for the shape of the global production function, and technical change augments both factors in the long run. Furthermore, the elasticity of substitution between capital and labor may exceed unity and thus yield endogenous growth.global production function, technology frontier, CES, Pareto distribution, Clayton copula

Phillips curve instability and optimal monetary policy

This paper assesses the implications for optimal discretionary monetary policy if the slope of the Phillips curve changes. The paper first derives a ‘switching’ Phillips curve from the optimal pricing decision of a monopolistic firm that faces a changing cost of price adjustment. Two states exists, a state with a high cost of price adjustment that generates a ‘flat’ Phillips curve and a low-cost state that generates a relatively ‘steep’ curve. The second aspect of the paper constructs a utility-based welfare criterion. A novel feature of this criterion is that it has a relative weight on output gap deviations that is state dependent, so it changes with the cost of price adjustment. Optimal monetary policy is computed subject to the switching-Phillips curve under both ad-hoc and utility-based welfare criteria. The utility-based criterion instructs monetary policy to disregard the slope of the Phillips curve and keep its systematic actions constant across different states. This stands in contrast to the prescription coming under the ad-hoc criterion, which advises monetary policy to change its systematic behavior according to the slope of the Phillips curve.Phillips curve ; Monetary policy

Why the Fed should ignore the stock market

James B. Bullard and Eric Schaling study a simple, small dynamic economy which a policymaker is attempting to control with a Taylor-type monetary policy rule. The authors wish to understand the macroeconomic consequences of the policymaker’s decision to include the level of equity prices in the rule. They show that such a policy can be counterproductive because it can interfere directly with the policymaker’s ability to minimize inflation and output variability. In extreme cases, a policy of targeting equity prices can lead to an indeterminate rational expectations equilibrium and hence a more unpredictable form of volatility than would be achieved by maintaining a rule without asset prices included. They thus provide an important and novel theoretical reason why policymakers may wish to ignore equity market developments when setting monetary policy.Monetary policy ; Stock market ; Federal Open Market Committee

Internal Rationality, Imperfect Market Knowledge and Asset Prices

We present a decision theoretic framework in which agents are learning about market behavior and that provides microfoundations for models of adaptive learning. Agents are 'internally rational', i.e., maximize discounted expected utility under uncertainty given dynamically consistent subjective beliefs about the future, but agents may not be 'externally rational', i.e., may not know the true stochastic process for payoff relevant variables beyond their control. This includes future market outcomes and fundamentals. We apply this approach to a simple asset pricing model and show that the equilibrium stock price is then determined by investors' expectations of the price and dividend in the next period, rather than by expectations of the discounted sum of dividends. As a result, learning about price behavior affects market outcomes, while learning about the discounted sum of dividends is irrelevant for equilibrium prices. Stock prices equal the discounted sum of dividends only after making very strong assumptions about agents' market knowledge.learning, internal rationality, consumption based asset pricing

DSGE models and the Lucas Critique. A historical appraisal

This contribution to the history of the economic thought aims at describing how “Econometric Policy Evaluation: A Critique” (Lucas, 1976) has been interpreted through four decades of debates. This historical appraisal clarifies how Lucas’s argument is currently understood and discussed within the dynamic stochastic general equilibrium (DSGE) approach. The article illustrates how two opposite interpretations of the Lucas Critique arose in the early 1980s. On the one hand, a theoretical interpretation” has been championed by the real business cycle (RBC) approach; on the other hand, an “empirical interpretation” has been advocated by Keynesians. Both interpretations can be understood as addressing a common question: Do microfoundations imply parameters’ stability? Following the RBC theoretical interpretation, microfoundations do imply stability; conversely, for Keynesians, parameters’ stability (or instability) should be supported by econometric evidence rather than theoretical considerations. Furthermore, the article argues that the DSGE approach represent a fragile compromise between these two opposite interpretations of Lucas (1976). This is especially true for the recent literature criticizing the DSGE models for being vulnerable to the Lucas Critique