Increasing claims for soft tissue injuries in workers' compensation: Cost shifting and moral hazard

During the last decade, the distribution of workers' compensation claims has exhibited a marked shift towards soft tissue injuries such as sprains, strains, and low back claims. There are three possible explanations for this trend; (1) safety incentives induced by workers compensation or OSHA may have reduced other, traumatic claims; (2) the movement away from heavy manufacturing and the 1980 construction recession may have changed the underlying risk of a workplace injury; and (3) there has been moral hazard behavior on the part of workers and health care providers. Using a new data source and estimation framework, we find evidence that moral hazard response explains most of the 30% increase in the proportion of soft tissue injuries during the 1980s.     

Testing purchasing power parity: some evidence of the effects of transaction costs

Empirical tests of purchasing power parity often recognize the problems created by simultaneous equations, but seldom recognize the effects of measurement error or transaction costs. Presumably because most researchers believe that they are unimportant. We present evidence that shows that measurement error and transaction costs and create serious econometric problems for testing purchasing power parity. One effect of these problems is that conventional tests of purchasing power parity can accept PPP when predictive errors are relatively large and reject it when predictive errors are relatively small. Another effect is to bias test of cointegration toward accepting the null of no cointegration between exchange rates and relative price indexes. We also construct a simple model of the determination of exchange rates that shows how transaction costs lead to regression switiching.