Temporal delay,type of forewarning,and resistance to influence

Previous researchers have manipulated forewarning by providing premessage information about the topic and position of the upcoming communication, or the communicator's persuasive intent. Subjects in the present experiment were force-warned either 10 min prior to the communication, or just before the message began of the speaker's topic and position, persuasive intent, or topic only. As hypothesized, forewarning of the communicator's persuasive intent inhibited persuasion regardless of the length of the delay period, but forewarning of the topic and position required a delay in order to confer resistance to subsequent persuasion, suggesting that although both manipulations have been called “forewarning they may lead to reduced persuasion through different mechanisms. Foreknowledge of the source's topic, but not his position also increased resistance to persuasion when followed by a delay period. The results were discussed in terms of both cognitive and motivational mechanisms that may underly the persuasion inhibiting effects of forewarning.     

A recodification of the Palermo and Jenkins word-association norms

The Palermo and Jenkins (1964) word association norms were recodified, with responses alphabetically arranged, and related to the various levels of stimuli.     

Response selection in paired-associate learning

Ss were presented pairs of items on study cycles; on test cycles Ss were presented the stimulus items and required either to recall the correct response or to indicate the correct response from three alternatives. It was demonstrated that Ss who chose the correct responses from the alternatives tended to select from both stimulus and response compounds so that the association was between stimulus and response components. The amount of selection from the response compounds was comparable to that from the stimulus compounds.     

The importance of subject control in reinforcing brain stimulation

A comparison between the reinforcement strength of self-administered and externally imposed brain stimulation was undertaken. Rats performed on a chain schedule in order to receive brain stimulation, either selfadministered or imposed, during the second component of the chain. Response rates during the first component of the chain schedule indicated that self-stimulation was more reinforcing than imposed stimulation. In addition, contrast, both positive and negative, seemed to be present. It was concluded that reinforcement strength may be enhanced when the subject controls the presentation of reinforcement.     

The interpretation of a test validity coefficient in terms of increased efficiency of a selected group of personnel

The predictive efficiency of a test used to select personnel is defined in terms of total effectiveness of the group thus selected, as compared with chance selection. The formula developed requires the use of an estimate of the ratio of average effectiveness of men selected to the average effectiveness of men not selected by the test. The predictive efficiency of the test varies directly with the magnitude of this ratio and also directly with the percentage rejected.     

The theory of the estimation of test reliability

The theoretically best estimate of the reliability coefficient is stated in terms of a precise definition of the equivalence of two forms of a test. Various approximations to this theoretical formula are derived, with reference to several degrees of completeness of information about the test and to special assumptions. The familiar Spearman-Brown Formula is shown to be a special case of the general formulation of the problem of reliability. Reliability coefficients computed in various ways are presented for comparative purposes.     

The relation between the difficulty and the differential validity of a test

Using scores of 1200 students on a long test as a criterion, each of five subtests of different difficulty has maximum correlation with the criterion when the criterion is dichotomized at a value appropriate to the difficulty of the subtest. A 50-item test element is scored on an all-or-none basis with different standards for passing, and the percentage of passes for successive points on the criterion variable is computed. The Constant Method is applied to this relationship. The limen thus computed is a measure of difficulty, the dispersion is a measure of average (or total) validity, and the slope of the curve is a measure of differential validity. The difficulty of a test element is thus directly related to the maximum differential validity.