This study shows that residual variation can cause problems related to scaling in exponential random graph models (ERGM). Residual variation is likely to exist when there are unmeasured variables in a model--even those uncorrelated with other predictors--or when the logistic form of the model is inappropriate. As a consequence, coefficients cannot…

This study explores the influence of cognitive (knowledge and certainty) and psychosocial (social norms and efficacy) variables on youth's climate change-related behaviour, with the aim to create an empirically supported theoretical model for youth's choice to take action to mitigate climate change. This survey-based research was conducted with…

The aim of this study is to develop a valid and reliable instrument to assess why physics courses are perceived as one of the most difficult courses among high school students and to investigate the reasons why students have difficulty in learning physics through this scale. This study includes the development and validation studies of the…

In this era of high-stakes testing and accountability, curricula are viewed as catalysts to improve high school students' mathematics performances and a critical question is whether single subject or integrated curricula produce stronger student outcomes. This study was designed to investigate the effects of an integrated reform-based curriculum,…

Measurement scales developed using Thurstone and item-response theory (IRT) methods of scaling achievement tests for the same single-level data were compared for approximately 4,000 high school students taking the Iowa Tests of Educational Development in 1975. Results of both approaches indicate that variability increases as grade level increases.…