In the presence of uncertain lifetimes, social security has the characteristics of an annuity: a consumer pays a tax when young in exchange for receiving a social security benefit if he survives to be old. If consumers have identical ex ante mortality probabilities, then a fully funded social...

This paper presents a general equilibrium model with logarithmic preferences and technology. If the non-negativity constraint on bequests is strictly binding, then the bequest motive is characterized as inoperative. After determining the conditions for operative and inoperative bequest motives,...

This paper was an accidental re-issue of <a href="http://www.nber.org/papers/w8635">w8635</a>

The issue of dynamic efficiency is central to analyses of capital accumulation and economic growth. Yet the question of what operating characteristics of an economy subject to productivity shocks should be examined to determine whether or not it is efficient has not been resolved. This paper...

Capital investment decisions must recognize the limitations on the firm's ability later to sell off or expand capacity. This paper shows how opportunities for future expansion or contraction can be valued as options, how this valuation relates to the q-theory of investment, and how these options...

This paper attempts to give a structural interpretation to the distributed lag of sales on investment at the two-digit level in US manufacturing. It first presents a simple model which captures the various sources of lags and their respective implications. It then estimates the model, using both...

This paper presents an overview of current models of consumption and investment behavior. First, the stochastic implications of the permanent income model and empirical tests of these implications are discussed. Then the simple theoretical model is extended to include expenditure on consumer...

The Modified Golden Rule, which relates the rate of return on capital and the growth rate of the capital stock along long-run growth paths that maximize the utility of a representative infinitely-lived consumer, is invariant to the introduction of convex capital adjustment costs. Therefore,...

This paper introduces a utility function that nests three classes of utility functions: (1) time-separable utility functions; (2) "catching up with the Joneses" utility functions that depend on the consumer's level of consumption relative to the lagged cross-sectional average level of...

In an economy with identical infinitely-lived households that obtain utility from leisure as well as consumption, Chamley (1986) and Judd (1985) have shown that the optimal tax system to pay for an exogenous stream of government purchases involves a zero tax rate on capital in the long run, with...