Positive reinforcement of litter removal in the natural environment

Litter is an especially large and costly problem in unsupervised high-use recreational areas. This study investigated procedures to induce visitors to remove litter from an unsupervised U.S. Forest Service area in which signs attached to two litter stations instructed people to pick up and deposit litter. A small sum of money or chances on a larger sum given for participation usually resulted in more bags of litter being picked up per week. Although only a small proportion of the area's users participated in the project, ground surveys indicated the areas sampled were somewhat freer of litter during the payment condition. The results suggest that small monetary rewards may be a promising approach to litter control in unsupervised as well as supervised areas.     

Free-time as a reinforcer in the management of classroom behavior

Six subjects, comprising one class at a school for the deaf, were given reinforcement consisting of time free from school work for remaining seated in the classroom. As a result, the frequency of leaving their chairs was sharply reduced. A second procedure presented free-time not contingent on remaining seated. Little change was seen in the already lowered response rate. An extension of the time required to be seated with corresponding reduction in the number of daily free-time periods did not reduce the effectiveness of the procedure. A one-day observation after six weeks indicated that the procedure was still effective. A one-day contingency reversal, requiring subjects to leave their chairs at least once during each seated period in order to receive free-time, substantially raised the frequency of out-of-seat responses.     

Analysis of potentiation and overshadowing effects in the instrumental performance of pigeons

In each of two experiments, pigeons were trained on a multiple VI (variable interval) schedule with a 3-s delay of reinforcement. Different components were associated with different key colors. Experiment 1 (stage 2) confirmed a previous finding that the response rate is higher in a component having a signal (illumination of the houselight) filling the delay interval than in a component lacking the signal. This potentiation effect was replaced by an overshadowing effect (i.e., the rate was low in the signaled component) when in stage 1 of Experiment 1 the birds received concurrent experience of a component containing houselight presentations not correlated with reinforcement. In Experiment 2 it was found that this overshadowing effect was abolished when the signal used was the presentation of a pattern on the response key rather than illumination of the houselight. These results are interpreted in terms of an interaction between the rate-enhancing properties of the signal (perhaps a consequence of its conditioned reinforcing power) and the tendency of the signal in some conditions to evoke behavior that competes with the response being recorded.     

A Framework and Themes for Social Network Intervention

This paper is concerned with the development and application of social network concepts in clinical practice. A framework of network levels and sets for ordering data and observations is proposed; the phenomenon of truncated networks is considered and two emphases in network intervention (gathering and connecting forms) are proposed to conceptualize network characteristics and practice that follows from such characteristics. A number of current examples of network practice are placed within the framework, and several advantages of utilizing a network perspective as a complement to existing models of family therapy are noted.     

Anxiety and aggression of high and low assertive persons following conflict

This experiment examined changes in anxiety and differences in aggression for high and low assertive women when different degrees of conflict were encountered. As predicted, low assertive women were intially more uneasy or anxious than high assertive women when they were placed in a conflictual situation. When the level of actual conflict was low, the level of anxiety of low assertive women decreased. However, when the actual level of conflict was high the anxiety level of low assertive women remained unchanged. These results were taken as support for the fear of conflict hypothesis which predicted that the reduction in anxiety for low assertive persons is contingent upon whether or not the anticipated conflict is actually encountered. The results also indicated that high assertive women were not significantly more aggressive than low assertive women. This finding provided support for Galassi's position that assertiveness and aggression are distinct concepts.     

Influence of the cost of responding

In three experiments, the effect of costs associated with responding on judgments of the causal effectiveness of the response was examined. In Experiment 1, the temporal interval between outcomes was matched on a variable interval (VI) and a variable ratio (VR) schedule. When each response was made at some “cost,” and outcomes represented some “gain” for the subject, the rating of causal effectiveness for responses was higher on the VR than on the VI schedule. This relationship was absent when the outcome was a triangle Hash. In Experiment 2, the number of responses required per outcome on a VI and a VR schedule were matched, and responses on the VR schedule were rated as more causally effective. In Experiment 3, a VI-to-VR yoking procedure was used. With minimal response costs, judgments were similar on the VI and VR schedules, but with greater response costs, responses performed on the VR schedule were rated as more causally effective than those emitted on the VI schedule.