Altering contingencies to facilitate compliance with traffic light systems

The effects of altering light pattern sequences on driver compliance at a busy, urban intersection were explored. The baseline light timing sequences resulted in only 46.8% of drivers stopping at the yellow or red lights. Using an A-B-C design, we altered light pattern sequences that increased the probability of drivers stopping at the signals to 88.8% and 98.8%. These findings indicate that traffic light contingencies have potent effects in influencing driver behaviors at busy intersections. Following completion of the study, the traffic engineer approved the permanence of the light timing pattern that increased traffic rule compliance. Accident data collected before and after the light timing changes indicated a reduction in automobile accidents.     

ASSESSMENT OF STIMULUS PREFERENCE AND REINFORCER VALUE WITH PROFOUNDLY RETARDED INDIVIDUALS

We evaluated a procedure for identifying potential reinforcers with profoundly retarded individuals. In Experiment 1, six persons were repeatedly exposed to 16 stimuli, and approach behaviors to each stimulus were used to identify preferred and nonpreferred stimuli. In Experiment 2, we examined the reinforcing properties of preferred and nonpreferred stimuli by delivering them contingently on the occurrence of arbitrarily selected responses. Results revealed that the preferred stimulus conditions typically produced higher rates of responding than did either the baseline or the nonpreferred stimulus conditions, suggesting that the procedure can be used to assess reinforcer value for individuals with limited behavioral repertoires.     

Effects of Job Conditions on Worker Perceptions: Ambient Stimuli vs. Group Influence1

This study identifies the direct effects of objective job conditions on individual perceptions of job conditions. The assumptions that (1) group perceptions mediate the relationship between objective job conditions and individual perceptions of job conditions, and (2) group consensus enhances the relationship be-between group perceptions and individual perceptions were tested. Respondents were white, male, blue collar workers (N= 1240) in a tire and rubber manufacturing plant. Work groups (N= 156), consisting of four or more men on the same shift, in the same department, and who had the same supervisor, were identified. Objective job conditions included work group size, pay style, shift, and job technology. Group and individual perceptions of amount of work-load, role conflict, responsibility pressure, and intrinsic rewards were measured. The findings indicated that objective job conditions have important effects on individual perceptions of stressful and rewarding job conditions. Smaller work groups, and jobs that pay on an hourly rather than a piece-work basis, allow for some control over the pace of work, and allow for interaction among fellow workers resulted in higher levels of intrinsic rewards and lower levels of workload, role conflict, and responsibility pressures. An intriguing pattern appeared where, in perceptions involving interpersonal relations, work group influence was relatively more important than objective job conditions. When assessing task oriented aspects of work, objective job conditions were more important than group perceptions.