Rasch-Model Procedures Used To Build the JOCRF Vocabulary Item Bank. Technical Report 1990-3.

In an effort to improve the ways in which words are learned, the Johnson O’Connor Rosearch Foundation (JOCRF) is attempting to determine the difficulty level of all non-technical words in the English language. This item banking project entails: (1) identifying words that should be calibrated; (2) writing a test item for each word; (3) testing the item in public schools and private schools; and (4) calculating a series of statistics to assess the relative difficulty of a word and ple-%ce it on the JOCRF’s Vocabulary Scale. The vocabulary data base is composed of five data bases (ITEMS, USED, DISCUSS, STATS, and ALLSTATS) that are related to each other via various “key” fields. This report outlines the Rasch model statistical procedures used to determine the difficulty of a word. The rationale for using the Rasch model and a description of actual use of the statistical procedures are provided. The data base structure that the JOCRF uses to store the large quantities lf statistical and verbal data generated by the project is also described. Eight appendices are provided containing numerous figures and tables that supplement the text. A 36-item list of references is ii-luded. (SLD) Reproductions supplied by EDRS are the best that can be made from the original document.