Browsing by Author "Berberoglu, Giray"

Now showing 1 - 4 of 4

Can Computerized Adaptive Testing Work in Students' Admission to Higher Education Programs in Turkey?
(2017) Berberoglu, Giray; Kalender, Ilker
Admission into university in Turkey is very competitive and features a number of practical problems regarding not only the test administration process itself, but also concerning the psychometric properties of test scores. Computerized adaptive testing (CAT) is seen as a possible alternative approach to solve these problems. In the first phase of the study, a series of CAT simulations based on real students' responses to science items were conducted in order to determine which test termination rule produced more comparable results with scores made on the paper and pencil version of the test. An average of 17 items was used to terminate the CAT administration for a reasonable reliability level as opposed to the normal 45 items. Moreover, CAT based science scores not only produced similar correlations when using mathematics subtest scores as an external criterion, but also ranked the students similarly to the paper and pencil test version. In the second phase, a live CAT administration was implemented using an item bank composed of 242 items with a group of students who had previously taken the exam the paper and pencil version of the test. A correlation of.76 was found between the CAT and paper and pencil scores for this group. The results seem to support the CAT version of the subtests as a feasible alternative approach in Turkey's university admission system.
A cross-cultural comparison of the self-efficacy of middle-school mathematics teachers across Turkey and the United States
(2021) Sevgi, Sevim; Berberoglu, Giray; Cobb, Paul; Smith, Thomas M.
This study aims to compare teachers' self-efficacy across Turkish and American in-service middle-school mathematics teachers. The samples consist of 379 Turkish and 245 American in-service middle-school mathematics teachers. The self-efficacy questionnaire of the Middle-school Mathematics and the Institutional Setting of Teaching (MIST) scale was used in the study. The exploratory factor analysis revealed two dimensions of the self-efficacy measures across the American and Turkish teachers, such as classroom management and student support strategies. The measurement invariance property of the scale was evaluated before comparing the means of the groups. Despite the differences between the education systems, teachers' efficacy beliefs function quite similarly across the countries. The statistically significant mean differences in the subscale scores of efficacy measures between Turkish and American samples have no practical value. In both countries, teachers reported high level of confidence in efficacy beliefs in classroom management and student support strategies.
Linguistic Distance and Translation Differential Item Functioning on Trends in International Mathematics and Science Study Mathematics Assessment Items
(2021) Gokce, Semirhan; Berberoglu, Giray; Wells, Craig S.; Sireci, Stephen G.
The 2015 Trends in International Mathematics and Science Study (TIMSS) involved 57 countries and 43 different languages to assess students' achievement in mathematics and science. The purpose of this study is to evaluate whether items and test scores are affected as the differences between language families and cultures increase. Using differential item functioning (DIF) procedures, we compared the consistency of students' performance across three combinations of languages and countries: (a) same language but different countries, (b) same countries but different languages, and (c) different languages and different countries. The analyses consisted of the detection of the number of DIF items for all paired comparisons within each condition, the direction of DIF, the magnitude of DIF, and the differences between test characteristic curves. As the countries were more distant with respect to cultures and language families, the presence of DIF increased. The magnitude of DIF was greatest when both language and country differed, and smallest when the languages were same, but the countries were different. Results suggest that when TIMSS results are compared across countries, the language- and country-specific differences which could reflect cultural, curriculum, or other differences should be considered.
The Measurement Invariance of University Students' Ratings of Instruction
(2019) Kalender, Ilker; Berberoglu, Giray
The invariance in the scores of student rating of instruction was studied across high and low achieving classrooms. Achievement levels were determined by the two criteria such as self-reported expected grades and end of semester grades. The data included 625 classrooms. The equality of (i) factorial structure, (ii) factor loadings, (iii) item intercepts, and (iv) error variances of the 7 item rating scale were studied across these groups. With respect to self-reported expected grades, high and low achieving classes produced invariant scale characteristics except strict invariance. On the other hand, with respect to end of semester grades, full equality in item intercepts and error variances were not achieved. It seems that comparing the rating results across the classrooms and courses independent of the achievement levels of the students may be misleading especially for the high-stake decisions since the origin of the scale is not the same across high and low achieving groups.