Item Response Theory (IRT) introduces a parametric structure with two sets of parameters, one set of parameters is related to (testing) item characteristics while another set of parameters (latent trait) is related to examinees' ability which is also called IRT-score. First, this essay defines General Total Score (GTS) based on IRT parametric structure which is called IRT-based GTS. The comparison between IRT-based GTS and IRT-score is studied and discussed: IRT-based GTS is a measure for measuring examinees' performance based on their item responses while IRT-score is not. The decomposition expression of IRT-based GTS is also demonstrated. Finally, the concepts of Additivity and Measure are further discussed.

For full essay, please see

Preprint Item Response Theory and Its General Total Score