I discuss three common practices that obfuscate or invalidate the statistical analysis of randomized controlled interventions in applied linguistics. These are (a) checking whether randomization produced groups that are balanced on a number of possibly relevant covariates, (b) using repeated measures ANOVA to analyze pretest-posttest designs, and…

This paper explores the impact on teachers' self-efficacy to teach statistics from a graduate course aimed to develop teachers' knowledge of inferential statistics through engaging in data analysis using technology. This study uses qualitative and quantitative data from the Self-Efficacy to Teach Statistics Survey (Harrell-Williams et al., 2013)…

Peer victimization appears heritable, but it is unclear whether the traits that confer genetic risk require time and familiarity with a perpetrator to manifest or whether novel and brief interactions can lead to received aggression that demonstrates similar genetic risk. We examined 20-minute, peer-play interactions between 5-year-olds, pairing…

Many psychological processes are characterized by recurrent shifts between distinct regimes or states. Examples that are considered in this paper are the switches between different states associated with premenstrual syndrome, hourly fluctuations in affect during a major depressive episode, and shifts between a "hot hand" and a…

Consonant inventories are commonly drawn to assess the phonological acquisition of toddlers. However, the spontaneous speech data that are analysed often vary substantially in size and composition. Consequently, comparisons between children and across studies are fundamentally hampered. This study aims to examine the effect of sample size on the…

When identification of causal effects relies on untestable assumptions regarding nonidentified parameters, sensitivity of causal effect estimates is often questioned. For proper interpretation of causal effect estimates in this situation, deriving bounds on causal parameters or exploring the sensitivity of estimates to scientifically plausible…

In the criminal justice system, defendants accused of a crime are presumed innocent until proven guilty. Statistical inference in any context is built on an analogous principle: The null hypothesis--often a hypothesis of "no difference" or "no effect"--is presumed true unless there is sufficient evidence against it. In this…

Class size reduction policies have been widely implemented around the world in recent years. However, findings about the effects of class size on student achievement have been mixed. This study examines class size effects on fourth-grade mathematics achievement in 14 European countries using data from TIMSS (Trends in International Mathematics and…

This research aims to produce a learning instrument based on hypermedia which is valid, interesting, practical, and effective as well as to know its influence on the problem based skill of students Mathematical and Science Faculty, Makassar State University. This research is a research and development at (R&D) type. The development procedure…

Online instructional videos are becoming increasingly common within education. This study adopts a quasi-experimental 2 × 2 crossover design (control and experimental groups) to evaluate the efficacy of instructional videos to teach practical rehabilitation skills. The students performed practical sessions in class and were formatively assessed by…

There is consensus in the statistical literature that severe departures from its assumptions invalidate the use of regression modeling for purposes of inference. The assumptions of regression modeling are usually evaluated subjectively through visual, graphic displays in a residual analysis but such an approach, taken alone, may be insufficient…

Many theories of human cognition postulate that people are equipped with a repertoire of strategies to solve the tasks they face. This theoretical framework of a cognitive toolbox provides a plausible account of intra- and interindividual differences in human behavior. Unfortunately, it is often unclear how to rigorously test the toolbox…

Students (N = 313) in undergraduate leadership degree programs at Texas A&M University were surveyed to determine their leadership mindset using hierarchical and systemic thinking preferences. Significant differences in thinking were found between gender and academic classification. Male leadership students scored greater in hierarchical…

The study was aimed at studying the psychological strategies for resolving interpersonal conflict among administrators in Tertiary Institutions with Nnamdi Azikiwe University as the case study. Gaining an understanding of these strategies may assist administrators of educational programs in handling interpersonal conflicts in more constructive and…

This study investigated the effects of proximal and distal constructs on adolescent's academic achievement through self-efficacy. Participants included 482 ninth-and tenth-grade Norwegian students who completed a questionnaire designed to assess school-goal orientations, organizational citizenship behavior, academic self-efficacy, and academic…