Trees and diagrams of decomposition

We introduce here and investigate the notion of an alternative tree of decomposition. We show (Theorem 5) a general method of finding out all non-alternative trees of the alternative tree determined by a diagram of decomposition.     

Choice between Delayed Reinforcers: Interaction between Delay and Deprivation Level

Choice between two reinforcers differing in magnitude and delay was investigated in rats maintained at 80% ( n = 10) or 90% ( n = 10) of their free-feeding body weights using discrete-trials adjusting-delay schedules in which the two reinforcers (S\[mall] and L\[arge]) were associated with different levers. In each phase of the experiment the delay to the smaller reinforcer ( dS ) was held constant, and the delay to the larger reinforcer ( dL ) was varied in accordance with the distribution of choices in successive blocks of trials. The value of dS was varied across the four phases of the experiment (2, 4, 8, and 2 sec). When dS was 2 sec, the mean value of dL was higher in the rats maintained at 80% than in those maintained at 90% of their free-feeding body weights. When dS was increased, the value of dL increased in both groups; however the effect of deprivation level was abolished. The results are consistent with a model of choice that posits hyperbolic relations between reinforcer value and reinforcer magnitude, and between reinforcer value and delay of reinforcement.     

Alliance and Group Cohesion in Relationship Education

Relationship education programs have been shown as an effective way to increase relationship functioning. There is less known about how process factors, such as alliance with the leader or group dynamics, affect outcomes in these interventions. We examined group cohesion and alliance with the leader in a relationship education program tailored for individuals. Specifically, we examined whether participants' ratings (n = 126) of the group cohesion and alliance with the leader were associated with changes in relationship adjustment, relationship confidence, and communication quality from pre‐ to postintervention. The results demonstrated that participants' perceptions of the cohesion among the members in their relationship education group, but not the leader–participant alliance, made a significant contribution to the changes in participants' relationship functioning. These results suggest that the group dynamics among the members in the group are important ingredients in relationship education. Implications for relationship programs are provided.