Monica Costa Dias

Treatment Evaluation With Selective Participation and Ineligibles

Matching methods for treatment evaluation based on a conditional independence assumption do not balance selective unobserved differences between treated and nontreated. We derive a simple correction term if there is an instrument that shifts the treatment probability to zero in specific cases. Policies with eligibility restrictions, where treatment is impossible if some variable exceeds a certain value, provide a natural application. In an empirical analysis, we exploit the age eligibility restriction in the Swedish Youth Practice subsidized work program for young unemployed, where compliance is imperfect among the young. Adjusting the matching estimator for selectivity changes the results toward making subsidized work detrimental in moving individuals into employment.

How taxes and welfare distort work incentives: static, lifecycle and dynamic perspectives

Personal taxes and benefits affect the incentive to work over the lifecycle by altering income-age profiles, insuring against adverse shocks, and changing the returns to human capital. Previous work investigating the impact of taxes and benefits on work incentives has tended to ignore these dynamic considerations. In this paper, we use a dynamic model to show how a lifecycle perspective alters our impression of the effect of the tax and benefit system on female work incentives. We describe how work incentives change over the life and show how they depend on lifecycle circumstances. We also devise a forward-looking measure of work incentives that incorporates all the dynamic considerations likely to affect work decisions at any given age. We find that individuals experience considerable variability in work incentives across life that outweighs the variability across individuals. Changes pattern of family types across life is key to explaining these patterns: work incentives vary dramatically depending on family composition, and most women experience a number of different family types during the course of their lives. We also find that differences in family type are an important explanation for why static and forwardlooking PTRs diverge, though this is more to do with differences in how women in families with different compositions behave.

The impact of health on labour supply near retirement

Estimates of the effect of health on employment differ signi cantly from study to study due to differences in method, data, institutional background and health measure. We assess the importance of these differences using a unifi ed framework to interpret and contrast estimates of the impact of health on employment based on various measures of health and estimation procedures. This is done for the US and England. We fi nd that subjective and objective health measures, as well as subjective measures instrumented by objective measures produce similar estimates if a sufficiently large number of objective measures is used. Reducing the number of objective measures used compromises their ability to capture work capacity and biases estimates downwards. Failure to account for initial conditions leads to an overstatement of the effect of health on employment. We also find that a carefully constructed single index of subjective health yields estimates that are very similar to those obtained with multiple measures. Overall, declines in health can explain between 3% and 15% of the decline in employment between ages 50 and 70. These effects are larger among high-school dropouts and tend to drop with education; they are also larger in the US than in England. Finally, cognition has little added explanatory power once we also control for health, suggesting that cognition is not a key driver of employment at these ages.

The Dynamic Effects of Health on the Employment of Older Workers

Using data from the Health and Retirement Study (HRS) and the English Longitudinal Study of Ageing (ELSA), we estimate a dynamic model of health and employment. We estimate how transitory and persistent health shocks affect employment over time. In a first step we formulate and estimate a dynamic model of health. The procedure accounts for measurement error and the possibility that people might justify their employment status by reporting bad health. We find that health is well represented by the sum of a transitory white noise process and a persistent AR(1) process. Next, we use the method of simulated moments to estimate the employment response to these shocks. We find that persistent shocks have much bigger effects on employment than transitory shocks, and that these persistent shocks are long lived. For this reason employment is strongly correlated with lagged health, a fact that the usual cross sectional estimates do not account for. We also show that accounting for the dynamics of health and employment leads to larger estimates of the effect of health on employment than what simple OLS estimates of health on employment would imply. We argue that the dynamic effect of health on employment could be generated by a model with human capital accumulation, where negative health shocks slowly reduce the human capital stock, and thus gradually causes people to exit the labor market.