أثر معالجة القيم المتطرفة في بيانات اختبار تيمس الدولي لدراسة الرياضيات و العلوم TIMSS على دقة تقدير قدرات عينة من الطلبة الأردنيين وفقا لنظرية السمات الكامنة

Abstract EN

This study aims to identify the percentage of outlier values in Jordanian eighth graders scores in TIMSS international tests (TIMSS, 2011) and the impact of the method of treatment (deleting, keeping, replacement) in the students’ scores at TIMSS test in accuracy of the students’ abilities according to latent trait theory according used three-parameter logistic model, and pointed out the Outlier values by the Box-plot method which showed there are 34 outlier values at the Maths data percent of 6.40 %, (44) Outlier values in science percent of 8.29 % to achieve the aims of this study it used the data of TIMSS, 2011 for math’s and science.

The sample consisted of (531) students (male and female) from those who responded to the test sheet number (11), it used the trimmed mean in replacing the outlier values, and depended on the marginal maximum likelihood estimation for the accuracy of estimated students’ abilities, and it used the standard error for accuracy of estimating, the results showed that the method of deleting the outliers better and more successful, and the most successful method comparing with the methods (keeping and replacing) by treatment with the outlier values of students’ abilities in math’s and science subjects on the estimated students’ abilities and its accuracy.