Unidimensional IRT Item Parameter Estimates Across Equivalent Test Forms With Confounding Specifications Within Dimensions
Bibliographic Data
| ID | 20283776 |
|---|---|
| Authors | Ki Lynn Matlock (Oklahoma State University, Stillwater, OK, USA, corresponding author), Ronna C Turner (0000-0002-2984-7649, University of Arkansas at Fayetteville), Ronna Turner (University of Arkansas, Fayetteville, AR, USA) |
| Year | 2016 |
| Volume | 76 |
| Issue | 2 |
| Pages | 258-279 |
| Publication date | 2016-04-01 |
| Open Access | Yes |
| Type | ARTICLE |
| Venue | Educational and Psychological Measurement (JOURNAL) |
| Journal identifiers | ISSN: 0013-1644 • E-ISSN: 1552-3888 |
| Publisher | SAGE Publications (PUBLISHER • US) |
| DOI | 10.1177/0013164415589756 |
| PMID | 29795865 |
| OpenAlex | W1144230941 |
| Language | EN |
| Citations received | 1 |
| References cited | 13 |
When constructing multiple test forms, the number of items and the total test difficulty are often equivalent. Not all test developers match the number of items and/or average item difficulty within subcontent areas. In this simulation study, six test forms were constructed having an equal number of items and average item difficulty overall. Manipulated variables were the number of items and average item difficulty within subsets of items primarily measuring one of two dimensions. Data sets were simulated at four levels of correlation (0, .3, .6, and .9). Item parameters were estimated using the Rasch and two-parameter logistic unidimensional item response theory models. Estimated discrimination and difficulty were compared across forms and to the true item parameters. The average unidimensional estimated discrimination was consistent across forms having the same correlation. Forms having a larger set of easy items measuring one dimension were estimated as being more difficult than forms having a larger set of hard items. Estimates were also investigated within subsets of items, and measures of bias were reported. This study encourages test developers to not only maintain consistent test specifications across forms as a whole but also within subcontent areas
Correlation · Differential item functioning · Dimension (graph theory) · Econometrics · Equating · Item analysis · Item response theory · Psychometrics · Rasch model · Set (abstract data type) · Standardized test · Statistics · Test (biology) · Test score · Advanced Statistical Modeling Techniques · Computer Science · Mathematics · Optimal Experimental Design Methods · Psychology · Psychometric Methodologies and Testing
| Citations per year | 0.2 |
|---|---|
| Citation span | 2021 - 2021 (1) |
| Highly cited | No |