In social experiments, individuals, households, or organizations are randomly assigned to two or more policy interventions. Elsewhere, we have summarized 143 experiments completed by autumn 1996. Here, we use the information we have gathered on these experiments and findings from informal...

The theories of human capital and internal labor markets are used to analyze teacher mobility. With data for the San Diego school system, we find that (1) since teaching assignments within school systems do not differ in terms of salary, internal mobility of teachers is governed by such...

Background:This article describes eight flaws that occur in impact evaluations.Method:The eight flaws are grouped into four categories on how they affect impact estimates: statistical imprecision; biases; failure of impact estimates to measure effects of the planned treatment; and flaws that...

Background:Impact evaluations draw their data from two sources, namely, surveys conducted for the evaluation or administrative data collected for other purposes. Both types of data have been used in impact evaluations of social programs.Objective:This study analyzes the causes of differences in...

An important source of errors in transfer payments programs is the fraudulent misreporting of earnings received by recipients. We propose a model of the recipient's decision to report income and the expected penalties if caught engaging in fraud. We discuss several features of the detection and...