Using the Rasch model to validate stages of understanding the energy concept

In recent years, there have been efforts to bridge science education with developmental psychology to develop theories on students developing understanding of science concepts from elementary to high school and beyond. The present study intends to test one such theory on students developing understanding of the energy concept. The theory states that students develop understanding of the energy concept by going through the following qualitatively distinct stages: (a) energy as activity/work; (b) energy as sources/forms, (c) energy transfer, (d) energy degradation, and (e) energy conservation. Three classes, one each from 4th grade, 8th grade, and high school physics class (grades 10, 11, and 12), completed a performance assessment. Students' performances were scored based on three traits of energy understanding: attention capacity, qualitative relations, and quantitative relations; each of the traits was defined into five hierarchical levels consistent with the five stages of understanding the energy concept. The Many-Facet Rasch Measurement (MFRM) model was used to analyze the effects of rater scoring severity, students' stages of energy understanding (theta), and difficulties of energy understanding traits. Results show that there was a discontinuity among the stages of understanding the energy concept, supporting the theory on students developing the understanding of the energy concept.     

Using Rasch models to reveal contours of teachers' knowledge

Teachers' knowledge is usually categorised into subject matter (SMK) and pedagogical content knowledge (PCK). Previously, measurement instruments and consequent cognitive scales have been developed to assess students' and teachers' subject knowledge. A number of qualitative studies have explored teachers' pedagogical content knowledge. This study developed a means to investigate one aspect of PCK--teachers' awareness of their students' knowledge--using a combination of measurement and qualitative interpretation. We asked teachers to estimate on a Likert scale (and also describe qualitatively) the difficulty their pupils would have with test items which we had already scaled using data from their pupils. We then constructed, using various models, a "Teacher's collective Perception of Item Difficulty" (TPID) scale and contrasted this with the student's ability scale by comparing the two sets of item-difficulty parameters. The results were triangulated with qualitative data. We suggest the methodology is best supported by an Inverse Partial Credit Model (IPCM) but we compare the results across alternative Rasch models.     

A study on the validity of a task complexity measure for emergency operating procedures of nuclear power plants—Comparing task complexity scores with two sets of operator response time data obtained under a simulated SGTR

The appropriateness of the task complexity (TACOM) measure that can quantify the complexity of procedural tasks was validated in this study. To this end, two sets of task performance time data that have been extracted under the simulated steam generator tube rupture (SGTR) conditions of the reference nuclear power plant (NPP) A and B were compared with the associated TACOM scores. As a result, it was observed that two sets of task performance time data seem to be soundly explained by the associated TACOM scores. Although more additional activities should be conducted to clarify the appropriateness of the TACOM measure, the result of this study provides a crucial clue supporting that the complexity of emergency tasks stipulated in emergency operating procedures (EOPs) can be properly quantified by the TACOM measure.     

Simultaneous measurement of reading growth,gender, and relative-age effects: many-faceted Rasch applied to CBM reading scores

Reading growth, gender effects, relative-age effects, and reading probe difficulty for reading were simultaneously assessed on one linear scale. The reading measure chosen was the Curriculum Based Measurement (CBM), words-read-correctly. A sample of 1619 students in Grades Two through Seven was employed. There is growth in reading within all grades but decreasing growth with increasing grade level. There are consistent gender differences favoring girls but the differences are equivalent to only one month's growth. There is no consistent evidence of a relative-age effect across grades. Two strategies for linking data across grades were compared and found to produce results consistent with each other and individual grade results.     

Using the Rasch measurement model to investigate the construct of motor ability in young children

This paper reports the use of a Rasch measurement model, the Extended Logistic Model of Rasch (Andrich, 1988), to explore the construct of a general motor ability in young children. Data were collected from 332 five and six year old children performing 24 motor skills, including run, hop, balance and ball skills. The data were categorised based on threshold estimates provided by the measurement model. Gender differences in performances on items were hypothesised to contribute to initial item and person misfit for the total sample. The data for boys and for girls were separated and independently analysed resulting in improved item and person fit. Two different, unidimensional scales for boys and for girls were created.     

Using the Rasch model to develop a measure of second language learners' willingness to communicate within a language classroom

The purpose of this investigation was to use Rasch measurement to study the psychometric properties of a 34 item questionnaire designed to measure second language learners' willingness to communicate (WTC) in English inside their language class. 490 Japanese university students' responses to the questionnaire were subjected to a number of different analyses. The first involved a comparison of the category threshold estimates produced by the Rating Scale and Partial Credit models. The questionnaire's items were then evaluated according to how well they defined the willingness to communicate construct. The potential dimensionality of using items that involved different speaking and writing tasks/situations in order to gain a more comprehensive understanding of students' willingness to communicate was also investigated. Next there was an examination of the questionnaire's four-point scale to ensure that it captured meaningful differences in students' WTC. Finally, the questionnaire items were compared using differential item functioning to determine if second year students were more willing than first year students in any of the different speaking and writing tasks/situations. This investigation closes with some suggestions on how the WTC questionnaire can inform second language instruction and curriculum design.     

Using Rasch measurement to investigate the cross-form equivalence and clinical utility of Spanish and English versions of a diabetes questionnaire: a pilot study

The purpose of this research was to use Rasch measurement to study the psychometric properties of data obtained from a newly developed Diabetes Questionnaire designed to measure diabetes knowledge, attitudes, and self-care. Specifically, a methodology using principles of Rasch measurement for investigating the cross-form equivalence of English and Spanish versions of the Diabetes Questionnaire was employed. A total of fifty diabetes patients responded to the questionnaire, with 26 participants completing the English version. Analyses detected problems with the attitude items. We attributed the scaling problems to the use of negatively worded items with participants having generally low educational backgrounds. Analysis of the knowledge and self-care items yielded unidimensional variables with clinically meaningful item hierarchies that may have relevance to treatment protocols. Furthermore, the knowledge and the self-care items from the two versions of the Diabetes Questionnaire met our criteria for establishing cross-form equivalence and thus allow quantitative comparisons of person measures across versions. Limitations of the study and suggested refinements of the Diabetes Questionnaire are discussed.     

Using Rasch analysis to test the cross-cultural item equivalence of the Harvard Trauma Questionnaire and the Hopkins Symptom Checklist across Vietnamese and Cambodian immigrant mothers

A major challenge in conducting assessments in ethnically and culturally diverse populations, especially using translated instruments, is the possibility that measures developed for a given construct in one particular group may not be assessing the same construct in other groups. Using a Rasch analysis, this study examined the item equivalence of two psychiatric measures, the Harvard Trauma Questionnaire (HTQ), measuring traumatic experience, and the Hopkins Symptom Checklist (HSCL), assessing depression symptoms across Vietnamese- and Cambodian American mothers, using data from the Cross-Cultural Families (CCF) Project. The majority of items were equivalent across the two groups, particularly on the HTQ. However, some items were endorsed differently by the two groups, and thus are not equivalent, suggesting Cambodian and Vietnamese immigrants may manifest certain aspects of trauma and depression differently. Implications of these similarities and differences for practice and the use of IRT in this arena are discussed.     

Using numerical methods in the preliminary stage of design of structures of equipment and parameters of electron beam deposition of protective coatings on the surface of turbine blades

Translated from Fiziko-Khimicheskaya Mekhanika Materialov, No. 3, pp. 117–119, May–June, 1992.