Altruism, Spite and Competition in Bargaining Games

This paper shows that altruism may be beneficial in bargaining when there is competition for bargaining partners. In a game with random proposers, the most altruistic player has the highest material payoff if players are sufficiently patient. However, this advantage is eroded as the discount factor increases, and if players are perfectly patient altruism and spite become irrelevant for material payoffs.     

La psicología social en América latina: Desarrollo y tendencias actuales

Resumen

La calidad del testimonio de un testigo depende tanto de su exactitud como de su credibilidad. Sin embargo, hasta la fecha la mayor parte de las investigaciones sólo se habían ocupado de la exactitud de testigos y testimonios.

Partiendo del concepto de metamemoria se analizan las creencias sobre la memoria de los testigos, presentando dos estudios interrelacionados.

En el primero, en el que participan 333 sujetos, se ponen a prueba dos hipótesis: que las personas con experiencia en testimonio por su profesión (p. e. policías) poseen más ideas intuitivas acertadas sobre memoria de testigos que las personas sin esa experiencia; la segunda, que las personas con concimientos sobre memoria (p. e. estudiantes de psicología) poseer más ideas intuitivas ciertas sobre memoria de testigos que las personas sin esos conocimientos.

Los resultados del primer estudio apoyan solo la segunda hipótesis.

El segundo estudio, con 42 policías, valora la eficacia de un procedimiento para entrenar a policías como expertos en testimonio, con resultados positivos.     

Understanding preferences for tree attributes: the relative effects of socio-economic and local environmental factors

Urban plant biodiversity is influenced by both the physical environment and attitudes and preferences of urban residents for specific plant types. Urban residents are assumed to be disconnected from their immediate environment, and cultural and societal factors have been emphasized over environmental factors in studies of landscaping choices. However, we postulate that local climatic and environmental factors can also affect preferences for plant attributes. Therefore, spatial and temporal patterns in urban tree biodiversity may be driven not only by the direct effect of environmental variables on plant function, but also by the effect of environmental variables on attitudes toward trees and associated choices about which types of trees to plant. Here, we tested the relative effects of socio-economic and local environmental factors on preferences toward tree attributes in five counties in southern California in and surrounding Los Angeles, based on 1,029 household surveys. We found that local environmental factors have as strong an effect on preferences for tree attributes as socio-economic factors. Specifically, people located in hotter climates (average maximum temperature 25.1 °C) were more likely to value shade trees than those located in cooler regions (23.1 °C). Additionally, people located in desert areas were less likely to consider trees to be important in their city compared with people located in naturally forested areas. Overall, our research demonstrates the inherent connections between local environmental factors and perceptions of nature, even in large modern cities. Accounting for these factors can contribute to the growing interest in understanding patterns of urban biodiversity.     

North Americans' Attitudes Toward Illegal Drugs

Public opinion polls conducted from 1969 to 2003 found a variety of opinions on the use, possession, and legalization of marijuana. Public opinion about legalizing marijuana use is increasing, but it is also increasing toward harsher penalties for those who possess a small amount of marijuana. Public opinion regarding the legalization of illegal drugs appears to be influenced by the times. The majority of Americans increasingly believe that the country has made some progress in dealing with the problems of illegal drugs, but Americans are also reporting more difficulty within their families related to marijuana. This article examines trends based in public opinion polls on the use of marijuana in the United States and Canada and discusses the social and political history of marijuana and the biophysical effects, medical uses, definitions, and previous research related to marijuana.     

Evaluation case histories as a parallel to legal case histories: Accumulating knowledge and experience in the evaluation profession

Legal case histories are a basic and essential part of the law. It is proposed that evaluation case histories would be valuable to the evaluation profession in that they would serve both to accumulate knowledge and experience and as examples of how to do evaluations. Part I of the paper is a discussion of the nature, place and use of case histories in law. The format of a reported case, the use of cases by attorneys and how case decisions are reported and categorized are also discussed. Part II of the paper tries to envision the nature and use of evaluation case histories as a parallel to legal case histories. Matters discussed include the possible function and use of evaluation case histories, the difference between an evaluation report and an evaluation case history, information an evaluation case history could contain, and how case histories might be reported and categorized.     

Predictors of Quality of Life in Different Age Groups Across Adulthood

This study examines the Quality of Life (QOL) of 374 individuals from a generational perspective. Using a nonexperimental design and multiple regression analyses, the results indicated that social support is the highest preditor of QOL for all generations. As for specific generational groups, in addition to social support, income was observed as a QOL predictor for young adults; marital status was a significant predictor for the middle-aged adults, and income emerged as the important predictor for older adults. These results offer valuable insights for the planning and implementation of Intergenerational Education Programs with the aim of increasing QOL across adulthood.