Many-Facet Rasch Model's Application in the Evaluation of Test Validity
This paper uses Many-facet Rasch Measurement Model to investigate the validity of an English text translation exam. It studies three "Facets" in the exam: examinees, raters and rating items. Research results indicate that the ability of examinees is significantly different, but some examinees display inconsistent performance when translating the text. 1.33% of the examinees do not bring their competence into full play when translating some sentences, 7.34% of the examinees translate some sentences unexpectedly well, and 3% of the examinees may not finish all the sentences.