To reduce nonresponse bias in surveys, it has been suggested that researchers allocate additional fieldwork efforts to cases with low estimated response propensity. If these efforts are successful, nonresponse bias may be reduced by changing the variance of response propensities and hence the covariance between response propensities and variables…

Thus far, it is unclear how students can learn most effectively from their own errors. In this study, reflections on the rationale behind self-made errors are assumed to enhance knowledge acquisition. In a field experiment with pre/post/follow-up design, the authors practiced fractions with 174 seventh- and eighth-grade students who were randomly…

Our study investigated whether problem-oriented designed ecology lessons with phases of direct instruction and of open experimentation foster the development of cross-domain and domain-specific components of "experimental problem-solving ability" better than conventional lessons in science. We used a paper-and-pencil test to assess…