PHYSICIANS' COST SHIFTING BEHAVIOR: MEDICAID VERSUS OTHER PATIENTS

Much of the debate about rising health care costs in the United States centers on the notion of "cost shifting." Cost shifting is loosely defined as charging one set of patients a higher price to offset losses on another set of patients. One aspect of the cost shifting debate that the empirical work has ignored is whether or not doctors—as opposed to hospitals—practice cost shifting. The analysis here investigates this question using the Physicians' Practice Costs and Income Survey, 1983–1985 (PPCIS, expanded version)
Using variation across states in Medicaid reimbursements, the analysis finds that lower Medicaid reimbursements tend to lower the fees physicians charge, contradicting the standard cost shifting story. Evidence also suggests that lower Medicaid reimbursements tend to cause physicians to treat fewer Medicaid patients. These results are consistent with profit maximizing behavior for physicians and also with the hypothesis that physicians exert some monopoly power.     

Day-of-the-Week Effects in the Long-Run Performance of Initial Public Offerings

This study examines the influence of day-of-the-week patterns in security returns on long-run IPO underperformance. Comparisons are made between the IPOs in Ritter's [20] database, and a constructed set of matching firms based on SIC code and size, using NYSE, AMEX, and NASDAQ securities. It is found that virtually all of the IPO underperformance occurs on Mondays and Tuesdays and that the degree of underperformance significantly differs from other days. Thus, a common explanation may exist for the general day-of-the-week pattern in security returns and IPO long-run underperformance.     

Intraday Returns and the Frequency of Trading at the Ask on the Sydney Futures Exchange: A Research Note

This article documents and provides explanations for intraday patterns in returns for the Share Price Index (SPI) futures contract traded on the Sydney Futures Exchange (SFE). Consistent with overseas futures markets research, a positive and significant overnight return is documented. Unlike overseas futures markets, we find little evidence of an end of day price rise. Our evidence suggests that overnight returns for the SPI contract are largely driven by the way returns are typically measured, which ignores the fact that there is a significantly greater frequency of sellers at the market close and buyers at the start of the day. These patterns are consistent with hedging behaviour by futures traders with long positions in the underlying stock.     

Testing for a Structural Change in U.S. Wage Determination

Previous tests for structural changes (slope changes) and shifts (intercept changes) in the Phillips curve and union wage determination specify the date of structural change a priori. This article tests for structural changes and shifts without specifying the change point ex ante . The results support the belief that structural changes occurred in the early 1980s. Contrary to some previous research, however, the results do not support a structural shift in the Phillips curve.