Mixed-effects models are an analytic technique for modeling repeated measurement or nested data. This paper explains the logic of mixed-effects modeling and describes two examples of mixed-effects analyses using R. The intended audience of the paper is psychologists who specialize in cognitive development research. Therefore, the concepts and…

The potential influence of violent video games on youth violence remains an issue of concern for psychologists, policymakers and the general public. Although several prospective studies of video game violence effects have been conducted, none have employed well validated measures of youth violence, nor considered video game violence effects in…