We establish explicit socially optimal rules for an irreversible investment decision with time-to-build and uncertainty. Assuming a price sensitive demand function with a random intercept, we provide comparative statics and economic interpretations for three models of demand (arithmetic...

This paper presents an economic interpretation of the optimal “stopping” of perpetual project opportunities under both certainty and uncertainty. Prior to stopping, the expected rate of return from delay exceeds the rate of interest. The expected rate of return from delay is the sum of the...

The optimal investment policy for a standard multi-period mean–variance model is not time-consistent because the variance operator is not separable in the sense of the dynamic programming principle. With a nested conditional expectation mapping, we develop an investment model with time...

Empirically, ADF tests fail to reject the null hypothesis that sales are I(1). We build a model of inventory behavior that incorporates permanent sales shocks. Analytically, the model with I(1) sales implies that the variance ratio (of log production to log sales) is one in the long run,...

Standard real business cycle models are often unable to replicate three empirical facts: positive output in response to good news, stochastic volatility of macro variables, and asymmetric business cycles. This paper proposes a unified basis for understanding these facts in a tractable dynamic...

This paper assesses various capital and labor adjustment costs functions estimating a general equilibrium framework with Bayesian methods using US aggregate data. The estimation finds that the adjustment costs are convex in both capital and labor and allowing for their joint interaction is...

This paper studies the conditions under which an IT revolution may occur and have permanent effects on long-term growth. To this end, we construct a multi-sectoral growth model with endogenous embodied technical progress. The R&D sector expands the range of softwares. The capital sector produces...

We interpret the marginal welfare cost of capital income taxes as the present discounted value of consumption distortions. Such an asset market interpretation emphasizes the importance of the interest rate used to value future distortions, especially in the presence of uncertainty. We find that...

In the presence of capital accumulation the Taylor principle may not be sufficient for determinacy under reasonable parameter values. In this paper I consider a two-sector extension of the models used in the existing literature. I show that what matters for whether the Taylor principle is...

In this paper, I explain two “puzzles” that have been observed in firm level data. First, firms that display a high sensitivity of investment to cash flow (commonly believed to be an indicator of liquidity constraints) usually have large unutilized lines of credit which, presumably, could be...