Are the large measured returns to on-the-job computer-use productivity gains or the result of unobserved heterogeneity unrelated to productivity? We examine this issue with two large cross-sectional surveys from Germany.

The standard version of "q" theory, in which investment is positively related to marginal "q", breaks down in the presence of fixed costs of adjustment. With fixed costs, q is a non-monotonic function of investment. Therefore its inverse, which is the traditional investment function, does not...

The market value of corporate stock in the United States increased by nearly one trillion dollars between December 1994 and July 1995. This paper explores the distribution of the stock ownership, and hence the gains from the stock price rise, and what the rise in stock prices implies for...