This article offers an approach to examining differential item functioning (DIF) under its item response theory (IRT) treatment in the framework of confirmatory factor analysis (CFA). The approach is based on integrating IRT- and CFA-based testing of DIF and using bias-corrected bootstrap confidence intervals with a syntax code in Mplus.

In the present research, we attempted to manipulate noncontingent processing in reading, that is, mental activities not dependent on processing the words of the text. An important class of noncontingent processing is mind wandering, but noncontingent processing may include other task-related activities as well. In our study, participants read…

Purpose: This study compared attention control and flexibility in school-age children who stutter (CWS) and children who do not stutter (CWNS) based on their performance on a behavioral task and parent report. We used a classic attention-shifting paradigm that included manipulations of task goals and timing to test effects of varying demands for…

The aim of the study was investigation of the effect of twice application of the Group Investigation method at different intervals on improvement of the students' academic achievement and science process skills in teaching the science lesson. Method of the study was a quasi-experimental design. The study used Solomon Four-group Experimental Design…

Background: Evidence suggests that an insufficient fluid intake impairs cognitive performance. Drinking policies at schools--especially drinking during lessons--is a point of controversy. To provide a scientific base for this debate, more empirical evidence is needed on which aspects of fluid intake are crucial for cognitive performance. This…

This study investigated the effects of temporal distribution of practice on the learning and retention of Mandarin tonal word production. Eighty native English-speaking adults with no prior knowledge of a tonal language participated in this study. They were randomly assigned to four experimental conditions varying in intersession interval (ISI)…

The academic calendar contains national data on how the academic year is structured (beginning of the academic year, term times, holidays and examination periods). Differences between university and non-university study programmes are also highlighted. The information is available for 37 countries. [For the previous report "The Organisation…

Recent studies of semantic memory have investigated two theories of optimal search adopted from the animal foraging literature: Lévy flights and marginal value theorem. Each theory makes different simplifying assumptions and addresses different findings in search behaviors. In this study, an experiment is conducted to test whether clustering in…

We replicated and extended the study by Koegel, Dunlap, and Dyer (1980) by examining the effects of 3 intertrial-interval (ITI) durations on skill acquisition in 2 children with autism spectrum disorders. Specifically, we compared the effect of short (2 s), progressive (2 s to 20 s), and long (20 s) ITIs on participants' mastery of tacts or…

When behaviors are reinforced with a variable interval reinforcement schedule, reinforcement is available only after an unknown period of time. These types of reinforcement schedules are most useful for reinforcing slow and steady responding and for differentially reinforcing behaviors that are incompatible with some problematic behaviors. This…

We conducted a preliminary investigation of a randomized dependent group contingency to decrease disruptive behavior during hallway transitions. Two first-graders, identified by their classroom teacher, participated in this study. A multiple baseline across transitions was used to evaluate the effects of the randomized dependent group contingency…

Purpose: Translating exercise-science methodology for determination of muscle bioenergetics, we hypothesized that the temporal voice-use patterns for classroom and music teachers would indicate a reliance on the immediate energy system for laryngeal skeletal-muscle metabolism. It was hypothesized that the music-teacher group would produce longer…

This study examined optimal learning schedules for second language (L2) acquisition of a morphological structure. Sixty participants studied the simple and complex morphological rules of a novel miniature language system so as to use them for oral production. They engaged in four training sessions in either shorter spaced (3.3-day interval) or…

Research shows that assuming a test scale is equal-interval can be problematic, especially when the assessment is being used to achieve a policy aim like evaluating growth over time. However, little research considers whether teacher value added is sensitive to the underlying test scale, and in particular whether treating an ordinal scale as…

Moment-based estimators of the between-study variance are very popular when performing random effects meta-analyses. This type of estimation has many advantages including computational and conceptual simplicity. Furthermore, by using these estimators in large samples, valid meta-analyses can be performed without the assumption that the treatment…