On what and how is measured by some personality tests I: One indecent table
Konstantin Momirović, Ankica Hošek · Psihologija · 1998
Metric characteristics of 6 different personality tests consisting of different number of Likert's scales were analyzed. These tests were selected among the test population having good metric characteristics as assessed by classic psychometric methods. The tests were administered to the different samples of subjects taken from different populations with the number of testees ranging from 120 to 495. We have analyzed the metric characteristics of the total score defined by the first main component of the standardized items' results and by the first main component of the optimally scaled items' results. The method of the alternating smallest squares was used in order to maximize the informativness of thus obtained result. It was assessed that the optimal scaling of items' results significantly improves the metric characteristics of the tests but, in the majority of cases, this also changes the subject of their measurement. Since this is possible only when the relations between items' results are neither linear nor monotonous it was concluded that the total result in personality tests consisting of Likert's scales couldn't be properly determined under any linear model.