We analyze the determinants of replacement investment decisions in a contingent claims model with maintenance and operation cost uncertainty. We find that the optimal time between replacements is increasing in the volatility of cost, the purchase price of a new asset, and the corporate tax rate; and is decreasing in the systematic risk of cost, the salvage value of the asset, and the investment tax credit. The optimal time between replacements can either increase or decrease with an increase in the depreciation rate. Extensions of the model to examine the effects of technological and tax policy uncertainty on replacement investment decisions give intuitive, but striking results. Uncertainty about the arrival of a technological innovation that would decrease maintenance and operation cost results in a significant decrease in replacement investment. Uncertainty in a tax law change that would encourage investment decreases current investment; and uncertainty in a tax law change that would discourage investment increases current investment.

David C. Mauer, Lemma W. Senbet, The Effect of the Secondary Market on the Pricing of Initial Public Offerings: Theory and Evidence, The Journal of Financial and Quantitative Analysis, Vol. 27, No. 1 (Mar., 1992), pp. 55-79

Previous studies have found that positive abnormal stock returns are associated with corporate spin-offs and divestitures. Using a simplified model of the process of investor tax trading, we show that an improvement in the value of the tax-timing option component of securities prices is a likely contributing factor to those abnormal returns. The analysis indicates that the same phenomenon also may be part of the explanation for the generally higher returns observed for spin-offs than for divestitures, both when leverage is and is not present in the restructuring transactions.

Among the elements of value reflected in the prices of corporate securities are the taxtiming options associated with the opportunities for investors to tax manage their portfolios by deferring gains and taking losses. We show that the aggregate value of these taxtiming options for the securityholders of a firm will be enhanced when the firm has multiple classes of tradeable securities outstanding. For that reason, the inclusion of debt as well as equity in a firm's capital structure should raise the total market value of the firm. We further show that, under most likely circumstances, there will be an interior optimal degree of leverage that will maximize tax-timing option values.

We model the firm's decision to invest in liquid assets when external financing is costly. The optimal amount of liquidity is determined by a tradeoff between the low return earned on liquid assets and the benefit of minimizing the need for costly external financing. The model predicts that the optimal investment in liquidity is increasing in the cost of external financing, the variance of future cash flows, and the return on future investment opportunities, while it is decreasing in the return differential between the firm's physical assets and liquid assets. Empirical tests on a large panel of U.S. industrial firms support the model's predictions.