Two experiments were designed to detect frustration phenomena hitherto only observed in subhuman animals, frustration being defined as the omission of the response item after a correct anticipation in a partial reinforcement schedule. (Authors)

The interaction between age and conceptual tempo was a consistently significant finding. (Author)

From this study it might be concluded that the development of conservation of quantity cannot be explained by maturation. (Author)

Results suggest that biodata provide a reliable set of measures to be used in the prediction of need for approval in male college freshmen. (Authors)

The data on physical fitness, body attitude and self-concept support the contention that a healthy attitude progresses through the physical sphere. (Author)

Results of this study indicates a need for diverse and concrete social learning materials in the preschool environment. (Authors)

Experiment to determine whether the use of realistic materials would improve performance in a deceptive reasoning problem. (Authors)

An investigation to determine what essential role characteristics lead to successful music programs. (CB)

Experiments designed to investigate performance on a complex task as it varies with training. (Author)

Participation in the Head Start program has had a favorable effect on the program participants in all of the major areas of development covered by the pupil rating instrument used in this assessment. (Author)

Classifies experimental error into two main groups: systematic error (instrument, personal, inherent, and variational errors) and random errors (reading and setting errors) and presents mathematical treatments for the determination of random errors. (PR)

Finding supports the educational theory and practices of Montessori educators. (Authors)