ERIC Number: ED233057
Record Type: Non-Journal
Publication Date: 1983-Apr
Reference Count: N/A
LOGTRUE: A Computer Program for Test Equating with Item Response Theory.
Phillips, S. E.; Anderson, A. E.
The LOGTRUE program can be used to obtain a scale of equated raw scores for two tests with parameter estimates on a common item response theory scale. The program derives its name from the method of logistic true score equating described by Lord (1980). The method can be applied to two tests with overlapping items administered to different groups of examinees (anchor test approach) or to two non-overlapping tests administered to the same group of examinees (scaling test approach). The method requires equal ability distributions for the examinees completing the two tests being equated, or that parameter estimates for the items in the two tests be transformed to a common scale based on a subset of overlapping items. Equating then proceeds. LOGTRUE's input data are the output of the LOGIST or EQUATOR computer programs. Difficulty estimates and the effects of difficulty parameter outliers are examined. (CM)
Publication Type: Speeches/Meeting Papers; Reports - Descriptive
Education Level: N/A
Authoring Institution: N/A