On the perception of a class of bilaterally symmetric forms

Two experiments were performed to determine the manner in which people perceive a class of bilaterally symmetric forms. In the first experiment, paired, comparison dissimilarity judgments and unidimensional single stimulus ratings were collected from the Ss. The second experiment involved the collecting of semantic differential and paired comparison dissimilarity judgments from two groups of Ss. The judgments and ratings from both experiments were compared to each other and to a set of objective measures of the forms by a series of multivariate statistical techniques. It was found that three primary attributes, orientation, convexity-concavity, and curvature, accounted for the perceptual reports, but the manner in which the attributes were used differed for different response procedures and for the same response on different occasions.     

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.     

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.     

Factorial invariance and significance

It is shown that invariance requirements remove the indeterminacy in factor determination and lead to an integration of factorial studies with promise of considerable reduction in computational labor. The selection of significant primary factors is discussed, with special reference to Thurstone's simple structure criterion.     

Different ways to get the job done: comparing the effects of intellectual stimulation and contingent reward leadership on task‐related outcomes

Two experiments were conducted to compare the effects of intellectual stimulation and contingent reward leadership on performance, task enjoyment, and extra effort. Participants (N = 78 and N = 158) viewed one of three videos and performed an in‐basket exercise. Several interesting differences emerged. Across both studies, participants in the control and contingent reward leadership conditions generated more ideas than their counterparts in the intellectual stimulation condition. Additionally, participants reported more willingness to exert extra effort when the leader was either intellectually stimulating or emphasized contingent reward leadership, as compared to the control condition. Finally, while task enjoyment was higher in the contingent reward leadership condition than in the control condition in Study 1, no significant differences emerged among conditions for enjoyment in Study 2.