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Comparison of 1‐, 2‐, and 3‐Parameter IRT Models
Author(s) -
Harris Deborah
Publication year - 1989
Publication title -
educational measurement: issues and practice
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.158
H-Index - 52
eISSN - 1745-3992
pISSN - 0731-1745
DOI - 10.1111/j.1745-3992.1989.tb00313.x
Subject(s) - curse of dimensionality , estimation theory , item response theory , independence (probability theory) , model parameter , set (abstract data type) , mathematics , econometrics , computer science , statistics , psychometrics , programming language
This module discusses the 1‐, 2‐, and 3‐parameter logistic item response theory models. Mathematical formulas are given for each model, and comparisons among the three models are made. Figures are included to illustrate the effects of changing the a, b, or c parameter, and a single data set is used to illustrate the effects of estimating parameter values (as opposed to the true parameter values) and to compare parameter estimates achieved though applying the different models. The estimation procedure itself is discussed briefly. Discussions of model assumptions, such as dimensionality and local independence, can be found in many of the annotated references (e.g., Hambleton, 1988).