Testing If the Heterogeneity Distribution of a Randomized Experiment Changes during the Experimental Period: a Statistical Analysis of a Social Experiment
نویسندگان
چکیده
The paper considers statistical tests for determining if the heterogeneity distribution of the treatment group in a randomized experiment changes during the experimental period. Solving the problem is of practical interest since heterogeneity changes may indicate serious selection problems in the randomized experiment. To make the tests easily implementable in practice, we discuss estimating critical values, for which we use bootstrap. To asses the actual performance of the tests, we conduct simulation studies. Finally, the tests are applied to analyze a social experiment data set, which is the main goal of the present paper. Classification codes: C12, D31, D63.
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