Investigating cross-linguistic similarity ratings: A Rasch analysis

Abstract

A robust finding in psycholinguistics is that cognates and loanwords, which are words that typically share some degree of form and meaning across languages, provide the second language learner with benefits in language use when compared to words that do not share form and meaning across languages. This cognate effect has been shown to exist for Japanese learners of English; that is, words such as table are processed faster and more accurately in English because they have a loanword equivalent in Japanese (i.e., テーブル /te:buru/ ‘table’). Previous studies have also shown that the degree of phonological and semantic similarity, as measured on a numerical scale from ‘completely different’ to ‘identical’, also influences processing. However, there has been relatively little appraisal of such cross-linguistic similarity ratings themselves. Therefore, the present study investigated the structure of the similarity ratings using Rasch analysis, which is an analytic approach frequently used in the design and validation of language assessments. The findings showed that a 4-point scale may be optimal for phonological similarity ratings of cognates and a 2-point scale may be most appropriate for semantic similarity ratings. Furthermore, this study reveals that while a few raters and items misfitted the Rasch model, there was substantial agreement in ratings, especially for semantic similarity. The results validate the ratings for use in research and demonstrate the utility of Rasch analysis in the design and validation of research instruments in psychology.