RIM: A Random Item Mixture Model to Detect Differential Item Functioning

In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is assumed for the item difficulties such that the items may belong to one of two classes: a DIF or a non-DIF class. The crucial difference between the DIF class and the non-DIF class is that the item difficulties in the DIF class may differ according to the observed person groups while they are equal across the person groups for the items from the non-DIF class. Statistical inference for the RIM is carried out in a Bayesian framework. The performance of the RIM is evaluated using a simulation study in which it is compared with traditional procedures, like the likelihood ratio test, the Mantel-Haenszel procedure and the standardized p -DIF procedure. In this comparison, the RIM performs better than the other methods. Finally, the usefulness of the model is also demonstrated on a real life data set.     

Input-Based Approaches to Teaching Grammar： A Review of Classroom-oriented Research

INTRODUCTION There is now a substantial body of research that has investigated the role of form-focused instruction in assisting learners to learn the grammar of a second language (L2). Recent comprehensive surveys of this research have been provided by N. Ellis (1995), R. Ellis (1990; 1994; 1997), Larsen-Freeman and Long (1991), Long (1988), Spada (1997),     

Leisure Attitudes of Varsity Athletes vs. NonVarsity Athletes

Abstract

Students (N = 104) enrolled in four low fitness, one middle fitness, and one high fitness class in basic physical education classes at the University of Connecticut participated in a 4-week program of isometric exercises done with an adjustable nylon belt which was stabilized against various body segments. Low, middle, and high fitness classes were compared in the amount of improvement made in the 5 items in which significant gains had been made. The MWF classes which did 30 min. of isometric exercises for 12 class meetings were compared to the TTh classes which met for 8 class meetings and which did the same isometric exercise program and in addition did stretching exercises and ran a mile.

When all groups were treated together, mean gains of 1.1 in. in the vertical jump, .74 sec. in the agility run, .17 sec. in the 30-yd. dash, 151.9 lb. in the leg lift, and 57.0 lb. in the back lift were made. These were all significant at the 0.005 to the 0.0005 level. Small but significant gains were made in right and left grip, the Fait endurance hang, and the 380-yd. run. The low fitness classes made greater improvements in the leg lift, the vertical jump, and the agility run than did the middle or high fitness groups. The high fitness class made greater improvements in the back lift and in the 30-yd. dash than did the low or middle fitness classes. The classes which did only isometric exercises for a half-hour three times each week for 4½ weeks made greater mean gains in the vertical jump, the agility run, the 30-yd. dash and the back lift than did the classes which met for 60-min. periods twice each week for 4½ weeks and did stretching exercises and running in addition to the isometric exercises. However, the latter made greater gains in the leg lift.     

Continuous walking and time- and intensity-matched interval walking: Cardiometabolic demand and post-exercise enjoyment in insufficiently active,healthy adults

ABSTRACT

We compared cardiometabolic demand and post-exercise enjoyment between continuous walking (CW) and time- and intensity-matched interval walking (IW) in insufficiently active adults. Sixteen individuals (13 females and three males, age 25.3 ± 11.1 years) completed one CW and one IW session lasting 30 min in a randomised-counterbalanced design. For CW, participants walked at a mean intensity of 65–70% predicted maximum heart rate (HR_max). For IW, participants alternated between 3 min at 80% HR_max and 2 min at 50% HR_max. Expired gas was measured throughout each protocol. Participants rated post-exercise enjoyment following each protocol. Mean HR and V˙O₂ showed small positive differences in IW vs. CW (2, 95%CL 0, 4 beat.min^?1; d = 0.23, 95%CL 0.06, 0.41 and 1.4, 95%CL 1.2 ml.kg^?1.min^?1, d = 0.36, 95%CL 0.05, 0.65, respectively). There was a medium positive difference in overall kcal expenditure in IW vs. CW (25, 95%CL 7 kcal, d = 0.58, 95%CL 0.33, 0.82). Post-exercise enjoyment was moderately greater following IW vs. CW (9.1, 95%CL 1.4, 16.8 AU, d = 0.62, 95%CL 0.06, 0.90), with 75% of participants reporting IW as more enjoyable. Interval walking elicits meaningfully greater energy expenditure and is more enjoyable than CW in insufficiently active, healthy adults.     

Interracial children

Changing lifestyles are having an impact on programs for young children. Recently these programs have adjusted to meet the needs of children from one-parent homes, broken homes, and teen homes. Now children of mixed racial and ethnic backgrounds are an ever-increasing phenomenon in programs. He is a parent of four interracial children and lectures on this topic     

Investigating inclusive education in primary schools in Ghana: what inclusive cultures,environment, and practices support implementation?

Schools create an inclusive environment and cultures and enact inclusive practices to cater for the learning and social needs of learners. Using an adapted Ghana Inclusive Education Monitoring Tool (IEMT), which is based on the Index for Inclusion, we collected data from 74 headteachers of primary schools. Data analysis involved percentages and frequencies of multiple-scaled items of the adapted IEMT. Findings revealed headteachers admit learners with special needs and disabilities (LwSEND) to set the stage for inclusion, while teachers accept these learners in schools. Collaborative cultures among teachers, parents, and other community stakeholders support inclusive education. While classrooms had somewhat good ventilation and lighting, school facilities were less accessible to all learners. Knowledge to adapt the curriculum and the flow of inclusive knowledge among teachers was limited. Suggestions to improve inclusive education include school-wide professional development for sharing inclusive knowledge, enhancing teachers' pedagogical competence and promoting supportive inclusive cultures.