Some Methods and Approaches of Estimating the Operating Characteristics of Discrete Item Responses Introduction
Fumiko Samejima · 2012
Psychology deals with hypothetical constructs such as ability, achievement, attitude, motivation, and so forth, which can only be observed indirectly, through an individual&s;s reactions to concrete stimuli. Yet these constructs prove to be useful in explaining human behavior. Latent Trait Theory is a family of theories and models which have been developed to measure hypothetical construct, or constructs, from individuals&s; reactions to particular stimuli. As a logical consequence of this objective, it is important to create a rationale which relates the individual&s;s reaction to the stimulus with his or her hypothetical construct. There may be an enormous number of factors eliciting his or her specific overt reactions to a stimulus, and, therefore, it is suitable, even necessary, to handle the situation in terms of the probabilistic relationship between the two. The smallest unit of such a stimulus is called an item in Latent Trait Theory, and the selected set of the individual&s;s reactions to an item is called a response.