Reporting sick: are sporting events contagious?
利用瑞典体育赛事期间男女请病假人数的差异变化，通过双重差分法发现男性为看电视而虚报病假，为道德风险提供了实证证据。
Abstract Moral hazard is easy to justify theoretically but difficult to detect empirically. Individuals may report sick due to illness as well as for moral hazard reasons. Potential abuse of the sickness insurance system in Sweden is estimated by comparing the change between the number of men and women who report sick during a popular sporting event and a preceding time period. Difference‐in‐differences estimates provide clear evidence that the number of men who reported sick increased in order to watch the sporting event on television. Copyright © 2004 John Wiley & Sons, Ltd.