Somayeh Kaveh; Ebrahim Khodaie; Amin Musavi; Ali Moghadamzadeh; jalil Younesi
Abstract
In order to facilitate the interpretation of raw scores, they are usually converted to scale scores. In some cases, these conversions are a series of nonlinear transformations that can affect the conditional standard error of measurement throughout the scale of score. Therefore, the purpose of this study ...
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In order to facilitate the interpretation of raw scores, they are usually converted to scale scores. In some cases, these conversions are a series of nonlinear transformations that can affect the conditional standard error of measurement throughout the scale of score. Therefore, the purpose of this study was to introduce methods for calculating the conditional standard error of measurement based on the strong true score theory. Furthermore, comparison of normalized and equipercentile nonlinear transformations on the raw scores of the academic achievements of the graduates of mathematical sciences in 2014 and their effect on conditional standard error of measurement was also conducted. So, in order to achieve these purposes, we used a sample of 3943 high school graduates of Mathematics and Physics in 2014 who had participated in national university entrance examination in 2015 randomly selected by National Organization of Educational Testing. The conditional standard error of measurement under these transformations was estimated based on the binomial procedure of Brennan and Lee (1999) and Chang (2006) method based on the beta-binomial distribution. The results of this study indicated that the conditional standard error of measurement of the Chang was smoother than binomial procedure, but in both methods the estimated errors are larger for middle points and smaller for extreme points. Additionally, the conditional standard errors of measurement of equipercentile were always less than normalized tranformation, so the equipercentile method found to be better than normalized transformation.
Mojtaba Jahanifar; Ebrahim Khodaie; jalil Younesi; Amin Musavi
Abstract
In order to the better interpreting and comparing scores in test batteries the raw scores in each test are converted to a common scale that called scale score. There are different Linear and nonlinear methods to convert raw scores to scale scores. Conventional methods of non-linear converting raw scores ...
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In order to the better interpreting and comparing scores in test batteries the raw scores in each test are converted to a common scale that called scale score. There are different Linear and nonlinear methods to convert raw scores to scale scores. Conventional methods of non-linear converting raw scores to scale scores are normalization and Arcsine methods. In This study that aimed to compare the standard error of measurement in non-linear converting methods we used 10000 random simulated sample data and 10000 random real sample data from Iran university entrance exam applicants.in order to compare converting methods conditional standard error of measurement that called CSEM, frequency charts and statistical indexes like moments was used. The results showed that both methods have different features. Although scores in both methods have high reliability and accuracy but Arcsine method reducing score error undulation for different score levels, also the mean of standard error of measurement for Arcsine scale scores was less than normalized scale scores.
