Macroeconomic Frictions: What have we Learned from the Real Business Cycle Research Programm ?

One interpretation of the RBC research program is that it was meant to identify and incorporate into dynamic general equilibrium models those market imperfections which are most relevant for macroeconomic theory and policy. This paper reviews the methodological basis for this interpretation. It then discusses the empirical foundations for some of the many frictions that have found their way into RBC models including efficiency wages, labour contracts, nominal price rigidities, limited market participation, imperfect competition and expectational errors. We find that the 'necessity' of these frictions is better established in some cases than in others. While one is lead to the prediction that the 'next neo-classical synthesis' will be a dynamic stochastic general equilibrium with frictions, it is premature to decide which specific friction will necessarily be taken on board.Business cycle; neo-classical synthesis; market frictions

The Macroeconomics of Delegated Management

We are interested in the macroeconomic implications of the separation of ownership and control. An alternative decentralized interpretation of the stochastic growth model is proposed, one where shareholders hire a self-interested manager who is in charge of the firm’s hiring and investment decisions. Delegation is seen to give rise to a generic conflict of interests between shareholders and managers. This conflict fundamentally results from the different income base of the two types of agents, once aggregate market clearing conditions are taken into account. An optimal contract exists resulting in an observational equivalence between the delegated management economy and the standard representative agent business cycle model. The optimal contract, however, appears to be miles away from standard practice: the manager’s remuneration is tied to the firm’s total income net of investment expenses, abstracting totally from wage costs. In order to align the interest of a manager more conventionally remunerated on the basis of the firm’s operating results to those of stockholder-workers, the manager must be made nearly risk neutral. We show the limited power of convex contracts to accomplish this goal and the necessity, if the manager is too risk averse (log or higher than log), of considerably downplaying the incentive features of his remuneration. The difficulty in reconciling the viewpoints of a manager with powers of delegation and of a representative firm owner casts doubt on the descriptive validity of the macro-dynamics highlighted in the representative agent macroeconomic model.business cycles, delegated management, contracting

Decentralizing the Stochastic Growth Model

The objective of this paper is to propose a number of alternative decentralized interpretations of representative agent style stochastic growth economies and to explore their implications for the generality of this model construct. Under our first interpretation, firms exist forever and undertake all multiperiod investment decisions while consumer-worker-investors only own financial claims to the firm's output. This contrasts with the more standard decentralization approach where firms exist on a period-by-period basis and consumer-workerinvestors have direct title to the economy's capital stock. Under our second interpretation shareholders hire a manager who undertakes the firm's investment decisions in conformity with his incentive contract. The time series properties of the shareholder-manager economy are seen to replicate those of the analogous representative agent economy if and only if the manager's contract assumes a specific form. This suggests the time series properties of an economy where incentive contracts such as stock option plans are pervasive will differ from those of more standard real business cycle models.stochastic growth model; business cycles; delegated management

The Macroeconomics of Delegated Management

We are interested in the macroeconomic implications of the separation of ownership and control. An alternative decentralized interpretation of the stochastic growth model is proposed, one where shareholders hire a self-interested manager who is in charge of the firm's hiring and investment decisions. Delegation is seen to give rise to a generic conflict of interests between shareholders and managers. This conflict fundamentally results from the different income base of the two types of agents, once aggregate market clearing conditions are taken into account. An optimal contract exists resulting in an observational equivalence between the delegated management economy and the standard representative agent business cycle model. The optimal contract, however, appears to be miles away from standard practice: the manager's remuneration is tied to the firm's total income net of investment expenses, abstracting totally from wage costs. In order to align the interest of a manager more conventionally remunerated on the basis of the firm's operating results to those of stockholder-workers, the manager must be made nearly risk neutral. We show the limited power of convex contracts to accomplish this goal and the necessity, if the manager is too risk averse (log or higher than log), of considerably downplaying the incentive features of his remuneration. The difficulty in reconciling the viewpoints of a manager with powers of delegation and of a representative firm owner casts doubt on the descriptive validity of the macro-dynamics highlighted in the representative agent macroeconomic model.business cycles; delegated management; contracting

Discrete Choices under Social Influence: Generic Properties

We consider a model of socially interacting individuals that make a binary choice in a context of positive additive endogenous externalities. It encompasses as particular cases several models from the sociology and economics literature. We extend previous results to the case of a general distribution of idiosyncratic preferences, called here Idiosyncratic Willingnesses to Pay (IWP). Positive additive externalities yield a family of inverse demand curves that include the classical downward sloping ones but also new ones with non constant convexity. When j, the ratio of the social influence strength to the standard deviation of the IWP distribution, is small enough, the inverse demand is a classical monotonic (decreasing) function of the adoption rate. Even if the IWP distribution is mono-modal, there is a critical value of j above which the inverse demand is non monotonic, decreasing for small and high adoption rates, but increasing within some intermediate range. Depending on the price there are thus either one or two equilibria. Beyond this first result, we exhibit the generic properties of the boundaries limiting the regions where the system presents different types of equilibria (unique or multiple). These properties are shown to depend only on qualitative features of the IWP distribution: modality (number of maxima), smoothness and type of support (compact or infinite). The main results are summarized as phase diagrams in the space of the model parameters, on which the regions of multiple equilibria are precisely delimited.Comment: 42 pages, 15 figure

Executive Compensation: The View from General Equilibrium

We study the dynamic general equilibrium of an economy where risk averse shareholders delegate the management of the firm to risk averse managers. The optimal contract has two main components: an incentive component corresponding to a non-tradable equity position and a variable 'salary' component indexed to the aggregate wage bill and to aggregate dividends. Tying a manager's compensation to the performance of her own firm ensures that her interests are aligned with the goals of firm owners and that maximizing the discounted sum of future dividends will be her objective. Linking managers' compensation to overall economic performance is also required to make sure that managers use the appropriate stochastic discount factor to value those future dividends.incentives; optimal contracting; stochastic discount factor

A Note on NNS Models: Introducing Physical Capital; Avoiding Rationing

This note makes two comments on recent NNS models. First, it disputes the way physical capital has been introduced into these models arguing that this leads to the dubious postulate that the cost of adjusting physical capital stock is an order of magnitude lower than the cost of changing prices. Second it warns against a possible logical inconsistency whereby calibrated NNS models are implicitly assuming that some (price-constrained) firms are willing and able to sell their output below cost.New Neo-Classical synthesis; sticky prices; cost-of-adjusting capital; rationing

On the Consequences of State Dependent Preferences for the Pricing of Financial Assets

This paper introduces state dependent utility into the standard Mehra and Prescott (1985) economy by allowing the representative agent's coefficient of relative risk aversion to vary with the underlying economy's growth rate. Existence of equilibrium is proved and its asymptotic properties analyzed. This generalization leads to level dependent marginal rates of substitution, a property that sharply distinguishes this model from the standard construct. For very low coefficients of relative risk aversion, the equilibrium risk free and risky security returns are demonstrated to have volatilities and an associated equity premium that substantially exceed what is found in the data. This provides a contrasting perspective on the classic "equity premium puzzle."state dependent utility; equity premium; equity premium puzzle

Discrete Choices under Social Influence: Generic Properties

We consider a model of socially interacting individuals that make a binary choice in a context of positive additive endogenous externalities. It encompasses as particular cases several models from the sociology and economics literature. We extend previous results to the case of a general distribution of idiosyncratic preferences, called here Idiosyncratic Willingnesses to Pay (IWP).Positive additive externalities yield a family of inverse demand curves that include the classical downward sloping ones but also new ones with non constant convexity. When $j$, the ratio of the social influene strength to the standard deviation of the IWP distribution, is small enough, the inverse demand is a classical monotonic (decreasing) function of the adoption rate. Even if the IWP distribution is mono-modal, there is a critical value of $j$ above which the inverse demand is non monotonic, decreasing for small and high adoption rates, but increasing within some intermediate range. Depending on the price there are thus either one or two equilibria.Beyond this first result, we exhibit the {\em generic} properties of the boundaries limiting the regions where the system presents different types of equilibria (unique or multiple). These properties are shown to depend {\em only} on qualitative features of the IWP distribution: modality (number of maxima), smoothness and type of support (compact or infinite).The main results are summarized as {\em phase diagrams} in the space of the model parameters, on which the regions of multiple equilibria are precisely delimited.discrete choice; social influence; externalities; heterogeneous agents; socioeconomic behavior