Identification of the Effects of Dynamic Treatments by Sequential Conditional Independence Assumptions

This paper approaches the dynamic analysis of the effects of training programs for the unemployed in West Germany, or in general the effects of sequences of interventions, from a potential outcome perspective. The identifying power of different assumptions concerning the connection between the dynamic selection process and the outcomes of different sequences is discussed. When participation in the particular sequence of programs is decided period by period depending on its success so far, many parameters of interest are no longer identified. Nevertheless, some interesting dynamic forms of the average treatment effect are identified by a sequential randomization assumption. Based on this approach, we present some new results on the effectiveness of West-German training programs.