Self-reinforcement: Impact of instructions,criterion setting,and tangible rewards

This investigation was designed to ascertain the effects of instructions, criterion setting, and the presence of tangible rewards on the self-reinforcement process. Fifty-two third- and fourth-grade subjects were assigned to one of four treatment groups: (a) stringent instructions/criterion setting/tangible reward, (b) stringent instructions/criterion setting/no tangible reward, (c) nonstringent instructions/criterion setting/tangible reward, and (d) nonstringent instructions/no tangible reward. In the stringent-instruction conditions, subjects received social reinforcement for selecting stringent performance criteria, whereas in the non-stringent-instruction conditions, social reinforcement was withheld. Subjects in the tangible-reward groups were allowed to select a prize following the successful completion of their self-selected work performance. Subjects in the no-tangible-reward groups received no prizes for their work. All subjects performed an arithmetic task in which the number of correct problems completed, number of problems attempted, and time at task served as dependent variables across five reinforcement and two extinction trials. The results suggest that the condition of stringent instructions, criterion setting, and tangible reward was more effective in producing behavior change than the other three conditions. Perceived task difficulty and previous achievement on arithmetic task performance were shown to affect criteria selected and mathematical performance. The results are discussed in light of the contributory role of instructions, criterion setting, and tangible rewards on the self-reinforcement procedure.This study is based on a doctoral dissertation submitted to the Faculty of Arts and Sciences at the University of Pittsburgh by Helen L. Evans. Dr. Russell T. Jones was the dissertation committee chairperson. It was partially funded by an American Psychological Association Minority Fellowship awarded to the first author. Special thanks are extended to the committee members, Drs. Lloyd Bond, Robert Glaser, Johnny Matson, and Samuel M. Turner, for their assistance. The authors would like to thank Thomas DeVoge, Paul Karoly, and Samuel M. Turner for reading and commenting on an early draft of this study. Portions of this paper were presented at the 1982 APA convention.     

Psychophysical parameters of the perception of orally-retained liquid bulk

Bulk of liquid held in the mouth may be judged on its subjective volume. Over the range I ml-31 ml, scaling by the constant method and by ratio estimation yielded a Weber fraction which was not constant and decreased with stimulus magnitudes and a psychophysical power function with an exponent of 0.96. A “negative threshold” effect is reported.