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211.
Recent work using decontextualized economic games suggests that cooperation is a dynamic decision‐making process: Automatic responses typically support cooperation on average, while deliberation leads to increased selfishness. Here, we performed two studies examining how these temporal effects generalize to games with richer social context cues. Study 1 found that time pressure increased cooperation to a similar extent in games played with in‐group members and out‐group members. Study 2 found that time pressure increased cooperation to a similar extent in games described as competitions and games described as collaborations. These results show that previous positive effects of time pressure on cooperation are not unique to neutrally framed games devoid of social context and are not driven by implicit assumptions of shared group membership or cooperative norms. In doing so, our findings provide further insight into the cognitive underpinnings of cooperative decision making. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
212.
If a group of foragers distributes among resource patches according to the ideal free distribution, the relative number of foragers in each patch should match the relative amount of resource obtained there, unless deviations arise from factors such as incomplete information or interforager interference. In analogy to individual choice, such effects may produce undermatching—group distribution falling short of resource distribution—or overmatching—group distribution overshooting resource distribution. In the present experiments, a flock of about 30 pigeons distributed between two patches with continuous inputs of green peas. Competition was varied by changing the size or extent of the patches. When the patches were areas or troughs, some undermatching occurred. When the patches were small bowls, strong undermatching occurred. When travel was required to switch patches, undermatching decreased slightly. A visual barrier that prevented pigeons from seeing one patch from the other had no effect. Overall rate of food delivery, varied over a wide range, had no effect. It appeared that the mechanism of flock distribution depended on comparisons between patches that were successive rather than simultaneous. Although most pigeons participated in the experiments, and different pigeons participated to different extents, individual pigeons tended to be consistent in the extent of participation from session to session, suggesting the possibility that participation might reflect competitive ability. Examination of the preferences and switching of individual pigeons revealed no consistency within or across individuals. It appeared that the flock's distribution was a truly emergent phenomenon, in the sense that results at the level of the flock in no way paralleled behavior at the level of the individual. 相似文献
213.
John W. Schuster Ed.D. Timothy E. Morse Ed.D. Ann B. Griffen M.S. Tim Wolery B.S. 《Journal of Behavioral Education》1996,6(4):511-533
A multiple probe across behaviors design, replicated across participants, assessed the effectiveness of constant time delay in teaching appropriate peer reinforcement and grocery words to 3 elementary students with moderate intellectual disabilities. Additionally, pretests and posttests assessed the acquisition of the participants' observational learning (acquisition of peers' grocery words) and instructive feedback (related information supplied by the teacher in the consequent event). Results indicate that the participants learned (a) how to appropriately reinforce peers, (b) to read their grocery words, (c) some of the targeted stimuli of their peers, and (d) much of the instructive feedback that was associated with each of the grocery words. Maintenance data indicate that the participants maintained their target grocery words at high levels of accuracy. 相似文献
214.
M.A. Sharifi W. van den Toorn A. Rico M. Emmanuel 《Journal of Multi-Criteria Decision Analysis》2002,11(3):151-164
Increased population growth and urbanization, has caused increase in demand for land around the city of Cochabamba, which has led to encroachment into the National Park and the construction of illegal settlements. This has created a number of problems, some of which are the direct consequences of the new settlements in the ‘Tunari’ foothills. These settlements constitute a threat to the environment and people because of their location in flood risk and aquifer recharge areas. In response to this problem the city authorities are considering relocating the boundary between the National Park and the city. This study has focused on the design and evaluation of alternative locations for a sustainable boundary between the north of ‘Cochabamba City’ and the southern boundary of the ‘Tunari National Park’. In this process, a rational and systematic approach of collaborative‐decision‐making, supported by geographical information systems (GIS) and multicriteria evaluation (MCE) has been employed and evaluated. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
215.
Ying-yi Hong Robert S. Wyer Jr Candy P. S. Fong 《Asian Journal of Social Psychology》2008,11(3):187-195
Chinese participants were found less likely to social loaf when working in groups than did North Americans. This result was attributed mainly to the collectivism and individualism characterizing Chinese and North Americans, respectively. However, this explanation does not address how Chinese people's social loafing tendency may vary across situations. If Chinese participants are concerned about their relations with coworkers, they should be more likely to conform to the performance level of their coworkers. This prediction is in opposition to effort dispensability, which is usually found among North Americans, whereby individuals adjust their effort in reverse to that of their coworkers. Consistent with our prediction, findings from three studies revealed that Chinese participants tended to conform to the performance level of their coworkers when their performance is made public ( vs kept anonymous) and when they have high ( vs low) relational concerns. These findings have implications for unpacking nuanced cultural influences on behaviours. 相似文献
216.
A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed. 相似文献
217.
Primary prevention focuses on the reduction of risk factors. Children of mothers with an eating disorder are a proven “at risk” group, because children internalise their experiences. Prevention in the field of eating disorders has as yet only addressed children of seven or eight upwards and only in school‐based programs which did not incorporate mothers. This project targeted mothers with an eating disorder who had children under the age of thirteen. The hypothesis is that if these mothers can be encouraged to change damaging behaviour that their children are likely to model, we can attempt to break the cycle of dysfunction. This is a qualitative and quantitive research project, carried out with standardised measures and semi‐structured interviews before and after a nineteen week therapy group, with six and twelve month follow ups. The group consisted of eight mothers. This paper describes the group and provides a case study of one participant. The initial analysis suggests that the support of a therapeutic group allowed this mother enough space for reflection. She became aware of her dysfunctional behaviour and was able to begin to understand the underlying reasons behind it. This led to an improvement in her own Eating Disorder (ED) and she was subsequently able to make change in her responses to her children's needs. 相似文献
218.
Selective age-related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high- and low-anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well-known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age-related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory. 相似文献
219.
The ideal free distribution theory (Fretwell & Lucas, 1970) predicts that the ratio of foragers at two patches will equal the ratio of food resources obtained at the two patches. The theory assumes that foragers have \"perfect knowledge\" of patch profitability and that patch choice maximizes fitness. How foragers assess patch profitability has been debated extensively. One assessment strategy may be the use of past experience with a patch. Under stable environmental conditions, this strategy enhances fitness. However, in a highly unpredictable environment, past experience may provide inaccurate information about current conditions. Thus, in a nonstable environment, a strategy that allows rapid adjustment to present circumstances may be more beneficial. Evidence for this type of strategy has been found in individual choice. In the present experiments, a flock of pigeons foraged at two patches for food items and demonstrated results similar to those found in individual choice. Experiment 1 utilized predictable and unpredictable sequences of resource ratios presented across days or within a single session. Current foraging decisions depended on past experience, but that dependence diminished when the current foraging environment became more unpredictable. Experiment 2 repeated Experiment I with a different flock of pigeons under more controlled circumstances in an indoor coop and produced similar results. 相似文献
220.
Heavy competition in India in almost all product categories, due to diversification by large and medium companies and increased entry of multinationals, has restricted the growth of domestic companies. Previously, large companies enjoyed high profit margins by targeting premium priced products in the upper strata of Indian society. High levels of competition from equally reputed brands have not only decreased the companies' market share but also created price wars, reducing profit margins and limiting market growth. This has motivated companies to consider the lower classes and the rural segments, which they had previously ignored. By targeting these segments with products in small packs at lower price points, companies have experienced great success. At the same time, small packs also pose some challenges for the companies. This paper explains the importance of small packs for market expansion in various product categories within the Indian market, drawing on several examples to support the views of the authors. Copyright © 2004 Henry Stewart Publications. 相似文献