In studies of educational achievement, students' self-reported number of books in the family home is a frequently used proxy for social, cultural, and economic background. Absent hard evidence about what this variable captures or how well, its use has been motivated by strong associations with student outcomes. I show that these associations rest…

TIMSS and PIRLS assess representative samples of students at regular intervals, measuring trends in student achievement and student contexts for learning. Because individual students are not tracked over time, analysis of international large-scale assessment data is usually conducted cross-sectionally. Gustafsson (2007) proposed examining the data…

Research on effects of home computer use on children's development of cognitive abilities and skills has yielded conflicting results, with some studies showing positive effects, others no effects, and yet others negative effects. These studies have typically used non-experimental designs and one of the main reasons for the conflicting results is…