In peer nomination research, individuals who do not provide nominations (nonparticipants) are often included on rosters as potential nominees. This can present ethical questions regarding informed consent, but psychometric consequences of excluding nonparticipants from rosters are unknown. In this investigation, Study 1 simulated both random and…

Worldwide, the interest of policy-makers in participating in studies from the International Association for the Evaluation of Educational Achievement (IEA), such as Trends in International Mathematics and Science Study (TIMSS) has been growing rapidly over the past two decades. These studies offer the opportunity to relate the teaching and…

Visuals and graphics have been used for communicating complex ideas since 1786 when William Playfair first invented the line graph and bar chart. Graphs and charts are useful for interpretation and making sense of data. For instance, John Snow's scatter plot helped pinpoint the source of a cholera outbreak in London in 1854 and also changed…

How many students repeat a grade each year? How do retention rates vary across states and over time? Despite extensive research on the predictors and consequences of grade retention, there is no systematic way to quantify state-level retention rates; even national estimates rely on imperfect proxy measures. We present a conceptually simple…

Randomized controlled trials (RCTs) are widely considered to be the gold standard in evaluating the impacts of a social program. When an RCT is infeasible, researchers often estimate program impacts by comparing outcomes of program participants with those of a nonexperimental comparison group, adjusting for observable differences between the two…

The Second International Conference on Educational Data Mining (EDM2009) was held at the University of Cordoba, Spain, on July 1-3, 2009. EDM brings together researchers from computer science, education, psychology, psychometrics, and statistics to analyze large data sets to answer educational research questions. The increase in instrumented…

This article reports a synthesis of intervention studies conducted between 1994 and 2004 with older students (Grades 6-12) with reading difficulties. Interventions addressing decoding, fluency, vocabulary, and comprehension were included if they measured the effects on reading comprehension. Twenty-nine studies were located and synthesized.…

Much has been written about the value of teacher research for inservice teachers. Despite the existence of several studies affirming these words, studies that richly describe how student teachers learn to do teacher research and then investigate the impact of inquiry on student teachers and teacher educators, particularly in culturally and…