Using self-organizing map and rating scale model in examining internal structure of scales

This study compares the psychometric properties of scales developed using Exploratory Factor Analysis (EFA), Self-Organizing Map (SOM), and Andrich's Rating Scale Model (RSM). Data for the research were collected by administering the "Statistical Attitude Scale" trial form, previously used in a separate study, to 808 individuals. First, EFA, SOM and RSM were applied to decide the number of dimensions of the scale, and to select items. Subsequently, Confirmatory Factor Analysis (CFA) was used to the forms obtained from different methods and their CFA fit indices were compared. The analysis revealed variations in the number of dimensions and item distribution across different methods. Results indicated that the form generated using SOM exhibited the highest fit indices. Furthermore, the CFA fit indices of the form created with RSM were found to be satisfactory, offering detailed insights into both items and individuals.