Shaping of three-man teams on a multiple DRL-DRH schedule using collective reinforcement

Five three-man teams were conditioned to a multiple DRL-DRH schedule during five daily sessions of 3 hr each. The teams were conditioned on the basis of their cumulative response rate regardless of the contributions of individual members. Two individually conditioned Ss were run under a similar schedule for comparison. Although all teams demonstrated some differentiation of response rate under the two legs of the schedule, this difference was not achieved as rapidly, nor was it as stable, as the differentiation in rates achieved in individually conditioned Ss. Team members displayed a variety of response rates as a result of collective team conditioning. Often, individual response rates interfered with obtainment of team reinforcement. The individual team members displayed little S^D control in comparison with the individually conditioned Ss. In general the results suggest that collective reinforcement is highly inefficient in comparison with procedures employing individual feedback.     

What do targeting positive views on ageing add to a physical activity intervention in older adults? Results from a randomised controlled trial

Objective: Physical activity is a key factor for healthy ageing, yet many older people lead a sedentary lifestyle. Traditional physical activity interventions do not consider the specific needs and views of older adults. As views on ageing are known to be related to health behaviours, the current study evaluates the effectiveness of prompting positive views on ageing within a physical activity intervention.

Design: Randomised controlled trial with three groups aged 65+: Intervention for physical activity with ‘views-on-ageing’-component (n?=?101; IGVoA), and without ‘views-on-ageing’-component (n?=?30; IG), and active control intervention for volunteering (n?=?103; CG).

Main outcome measures: Attitudes towards older adults and physical activity were assessed five weeks before intervention, two weeks, six weeks and 8.5?months after the intervention.

Results: Compared to the IG and CG, positive attitudes towards older adults increased in the IGVoA after the intervention. For IGVoA, the indirect intervention effect on change in activity via change in attitudes towards older adults was reliable.

Conclusion: A ‘views-on-ageing’-component within a physical activity intervention affects change in physical activity via change in views on ageing. Views on ageing are a promising intervention technique to be incorporated into future physical activity interventions for older adults.     

Einige Versuche zur Frage der harmonischen Zusammenstellung gefärbter Flächenstücke

Zusammenfassung Es werden einige Versuche mitgeteilt, die anzeigen, daß Farbenharmonien dann auftreten, wenn die Größen der gefärbten Flächenstücke so gewählt werden, daß die sog. Helligkeitsäquivalente im Verhältnis 11 stehen.