AN EXAMINATION OF THE CONTEXT EFFECT IN ITEM SAMPLING

Item sampling and/or multiple matrix sampling techniques have been recommended for a variety of purposes. For some of these purposes, it must be assumed that examinee performance on a set of items is unaffected by the conditions under which the items are taken (i.e., no context effect exists). In this paper factors that may lead to a context effect among high school students are discussed. The net effect of such factors on examinee scores for an English test and a mathematics test is investigated empirically. For the English test there was little support for the existence of a context effect, However, a definite context effect was found for the mathematics test.     

Discriminated avoidance vs classical conditioning: A two-phase model analysis

The acquisition of discriminated avoidance and classically conditioned leg flexions in dogs and of discriminated avoidance leg flexion in cats was examined via a two-phase model of conditioning. Classically conditioned Ss uniformly required two operators during Phase 2, with the limit of the CR operator being greater than that of the CR operator. Not all avoidance-trained Ss required two operators during Phase 2, but those who did also had a higher CR than CR operator limit. The CR operator limit was higher for avoidance than for classical training, while the change rate was greater for classical training. The avoidance behavior of cats paralleled that of the dogs. It was concluded that the data generally conformed to views of Hilgard and Marquis and, more recently, of Bolles, but were contrary to what would be expected from two-factor theory.     

A SECOND LOOK AT ANALYSIS OF VARIANCE ON DICHOTOMOUS DATA

The work of Lunney (1970) concerning the appropriateness of analysis of variance (ANOVA) techniques on dichotomous data is discussed and extended. Relations between standard statistical techniques for analyzing dichotomous data and ANOVA procedures are indicated. The need for usefulness of analyzing transformed data as opposed to direct analysis of dichotomous data are discussed. Required statistical procedures employing transformed data are outlined.