Examining the Pre-service School Principals' Impromptu Speech Skills with a Many-Facet Rasch Model.

The purpose of this study is to demonstrate an application of the many-facet Rasch model (MFRM) in evaluating the impromptu speech skills of pre-service principals in Taiwan. The findings showed that the topics of speech did not exhibit different difficulty measures. With respect to scoring criteria, time control was the most difficult aspect among the scoring criteria. Regarding gender difference in raters, female raters gave lower scores than male raters, but there was no statistical evidence for gender-related bias. However, raters exhibited statistically significant differences in rater severity. The results of this study demonstrates that the MFRM provides a scientific approach to assessment, which can reveal some useful diagnostic information from the original ordinal rating scores on impromptu speech.