Orlando and Thissen (2000) developed an item fit statistic for binary item response theory (IRT) models known as S-X[superscript 2]. This article generalizes their statistic to polytomous unfolding models. Four alternative formulations of S-X[superscript 2] are developed for the generalized graded unfolding model (GGUM). The GGUM is a…

Designed to analyze systematically the relative effects of different types of oral reading errors on comprehension, this instrument consists of a basic set (each with an easy and a hard version) of six stories. Every story is transformed so that it contains simulated errors of a particular type: (1) correct, (2) semantically related visually…

Seeks to assist instructors in recognizing two basic errors that can occur in processing student evaluation data on instructional development efforts; offers a research framework for future investigations of the error tendencies and related issues; and suggests ways in which instructors can confront and manage error tendencies in practice. (MBR)