Widhiarso, W., & Haryanta
This study investigates whether synonym and antonym tests measure similar domains of verbal abilities and have comparable psychometric performance. The data used in this study are subsets of the data collected during 2013-2014 graduate admission testing at Gadjah Mada University (UGM), using three forms of the Potensi Akademik Pascasarjana (PAPS) [Graduate Academic Aptitude Test]. Confirmatory factor analysis revealed that synonym and antonym tests assess similar domains of verbal abilities. A model integrating items from both tests to represent a single dimension better explained the data than a model separating the two tests into manifestations of different dimensions. High correlations among dimensions in unidimensional model showed interrelatedness for the domains of verbal abilities such as verbal knowledge, comprehension, and reasoning. Additional analysis using item-level analysis showed that antonym items tended to be more difficult than synonym items. This finding indicates that, although both tests assess similar content, responding to an antonym test requires more complex cognitive process than responding to a synonym test.
Key words: Synonyms; Antonyms; Verbal abilities; College admission test; Rasch analysis.