We develop a theory of warrants held by competitive warrantholders not constrained to exercise their warrants as one block; the theory also applies to convertible bonds held by competitive bondholders not constrained to convert their bonds as one block. We prove that the warrant (bond) price in each of the competitive equilibria is less than or equal to the price in an economy with the block constraint; and for at least one competitive equilibrium the warrant (bond) price equals the warrant (bond) price in the block-constrained economy. We illustrate the paths of competitive warrant exercise and bond conversion and conclude that under realistic assumptions they can be long.

The tax law confers upon the investor a timing option - to realize capital losses and defer capital gains. With the tax rate on long term gains and losses being about half the short term rate, the law provides a second timing option - to realize losses short term and gains long term, if at all. Our theory and simulation over the 1962–1977 period establish that taxable investors should realize long term gains in high variance stocks and repurchase stock in order to realize potential future losses short term. Tax trading does not explain the small-firm anomaly but predicts a seasonal pattern in trading volume which maps into a seasonal pattern in stock prices, the January anomaly, only if investors are irrational or ignorant of the price seasonality.

We embed the Sharpe-Lintner, two-parameter asset pricing theory in an intertemporal general equilibrium model. The investment opportunity set changes stochastically over time; in general the short-term and long-term interest rates and the distribution of the rate of return of the market portfolio are non-stationary. This non-stationarity, which is admissible in the Sharpe-Lintner model, has two implications: First, it may bias econometric methods which fail to explicitly take into account the non-stationarity. Second, the sequential application of the Sharpe-Lintner model in the discounting of stochastic cash flows becomes computationally complex and of little practical use.

Habit persistence in preferences and durability of consumption goods both imply time-nonseparability in the derived utility for consumption expenditures. We study a simple model with both effects. Lagged consumption expenditures enter the Euler equation, where habit persistence implies that their coefficients are negative and durability implies positive coefficients. Estimating the sign of the coefficients addresses the question of which effect is dominant. Earlier empirical work on monthly data supports the durability of consumption expenditures. We find evidence in monthly, quarterly, and annual data that habit persistence dominates the effect of durability.