The context of community-based interventions presents formidable problems for any evaluation analysis. Group-randomized studies do possess ideal properties in theory, but in practice, grouprandomization might not be a feasible alternative at all or group-randomized studies might be contaminated....

We characterize the bias of propensity score based estimators of common average treatment effect parameters in the case of selection on unobservables. We then propose a new minimum biased estimator of the average treatment effect. We assess the finite sample performance of our estimator using...

This paper considers the problem of making inferences about the effects of a program on multiple outcomes when the assignment of treatment status is imperfectly randomized. By imperfect randomization we mean that treatment status is reassigned after an initial randomization on the basis of...

Trust is a crucial component of social capital. We use an experimental moonlighting game with a representative sample of the U.S. population, oversampling immigrants, to study trust, positive, and negative reciprocity between first-generation immigrants and native-born Americans as a measure of...

We study experimentally the protection of property in five widely distinct countries - Austria, Mexico, Mongolia, South Korea and the United States. Our main results are that the security of property varies with experimental institutions, and that our subject pools exhibit significantly...

The IAB employment subsample is now available for researchers in a third, anonymised version. Following the so-called basic file and the regional file from the IAB employment subsample, which encompassed the years 1975 to 1990, the actualized version of the basic file covers now the years 1975...

Propensity score matching is a prominent strategy to reduce imbalance in observational studies. However, if imbalance is considerable and the control reservoir is small, either one has to match one control to several treated units or, alternatively, discard many treated persons. The first...

Currently available asymptotic results in the literature suggest that matching estimators have higher variance than reweighting estimators. The extant literature comparing the finite sample properties of matching to specific reweighting estimators, however, has concluded that reweighting...

In experimental designs with nested structures entire groups (such as schools) are often assigned to treatment conditions. Key aspects of the design in these cluster randomized experiments include knowledge of the intraclass correlation structure and the sample sizes necessary to achieve...