We study the consequences of hospital competition for Medicare beneficiaries' heart attack care from 1985 to 1994. We examine how relatively exogenous determinants of hospital choice such as travel distances influence the competitiveness of hospital markets, and how hospital competition interacts with the influence of managed-care organizations to affect the key determinants of social welfare—expenditures on treatment and patient health outcomes. In the 1980s the welfare effects of competition were ambiguous; but in the 1990s competition unambiguously improves social welfare. Increasing HMO enrollment over the sample period partially explains the dramatic change in the impact of hospital competition.

A recent paper in this Journal by Kaplan and Zingales reexamines a subset of firms from work of Fazzari, Hubbard, and Petersen and criticizes the usefulness of investment-cash flow sensitivities for detecting financing constraints. We show that the Kaplan and Zingales theoretical model fails to capture the approach employed in the literature and thus does not provide an effective critique. Moreover, we describe why their empirical classification system is flawed in identifYing both whether firms are constrained and the relative degree of constraints across firm groups. We conclude that their results do not support their conclusions about the usefulness of investment-cash flow sensitivities.

This paper tests the labor market signaling hypothesis for the General Educational Development (GED) equivalency credential. Using a unique data set containing GED test scores and Social Security Administration (SSA) earnings data, we exploit variation in GED status generated by differential state GED passing standards to identify the signaling value of the GED, net of human capital effects. Our results indicate that the GED signal increases the earnings of young white dropouts by 10 to 19 percent. We find no statistically significant effects for minority dropouts.