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Common Resource (common + resource)
Selected AbstractsA model of sequential effects in common pool resource dilemmasJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 1 2002David V. Budescu Abstract Experimental games are often used as models of social dilemmas in which small groups of players have unrestricted access to, and share, a common and finite resource of desirable goods in the absence of any binding coordination mechanism. Examples are fishing, hunting, and use of computational facilities. Experimental studies of social dilemmas employ different protocols of play that differ from each other in terms of the information available to the players when they register their requests from the common resource. In this study we focus on the sequential protocol, where each participant has complete information about his or her position and the total requests of the previous movers, and the positional protocol, where each player only knows his or her position, but has no information about the other's requests. Previous research has found a robust position effect: individual requests are inversely related to the players' positions in the sequence with the first mover requesting most, and the last mover requesting the least. In an attempt to characterize the nature and intensity of the position effect, we developed and tested a descriptive model with one free (individual specific) parameter. The parameter is estimated from the players' requests under the positional protocol (i.e. in the absence of any information about the other's requests) and, as such, quantifies the social norm of ,advantage of the early mover'. In a range of cases examined, including different group sizes, resource pool sizes, and positions, the model predicted very accurately individuals' requests in the sequential protocol (with full information about position and others' requests). Copyright © 2002 John Wiley & Sons, Ltd. [source] NATURAL RESOURCE EXPLOITATION UNDER COMMON PROPERTY RIGHTSNATURAL RESOURCE MODELING, Issue 1 2003MICHAEL R. CAPUTO ABSTRACT. Renewable natural resources such as ground-water, pastures and fisheries are often governed bycommon propertyrights in which members of a group jointlyown the exclusive use of the resource. We develop a formal model of a common propertycontract based on differential game theory and then use the model to examine (i) the incentives of individual users of the common resource; (ii) the resulting harvest and stock time paths; (iii) the local stabilityof the steady state; and (iv) the steadystate comparative statics. Moreover, we compare the qualitative properties of the common propertyregime to those generated under perfectlydefined private rights and open access. We show how common prop-ertyownership of natural resources can generate rent and be a second-best solution when private propertyrights are costly to establish. [source] Food mechanical properties in three sympatric species of Hapalemur in Ranomafana National Park, MadagascarAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Nayuta Yamashita Abstract We investigated mechanical dietary properties of sympatric bamboo lemurs, Hapalemur g. griseus, H. aureus, and H. (Prolemur) simus, in Ranomafana National Park, Madagascar. Each lemur species relies on bamboo, though previous behavioral observations found that they specialize on different parts of a common resource (Tan: Int J Primatol 20 1999 547,566; Tan: PhD dissertation 2000 State University of New York, Stony Brook). On the basis of these earlier behavioral ecology studies, we hypothesized that specialization on bamboo is related to differences in mechanical properties of specific parts. We quantified mechanical properties of individual plant parts from the diets of the bamboo lemur species using a portable tester. The diets of the Hapalemur spp. exhibited high levels of mechanical heterogeneity. The lemurs, however, could be segregated based on the most challenging (i.e., mechanically demanding) foods. Giant bamboo culm pith was the toughest and stiffest food eaten, and its sole lemur consumer, H. simus, had the most challenging diet. However, the mechanical dietary properties of H. simus and H. aureus overlapped considerably. In the cases where lemur species converged on the same bamboo part, the size of the part eaten increased with body size. Plant parts that were harvested orally but not necessarily masticated were the most demanding, indicating that food preparation may place significant loads on the masticatory apparatus. Finally, we describe how mechanical properties can influence feeding behavior. The elaborate procurement processes of H. simus feeding on culm pith and H. griseus and H. aureus feeding on young leaf bases are related to the toughnesses of protective coverings and the lemurs' exploitation of mechanical vulnerabilities in these plants. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] A study of women's knowledge regarding human papillomavirus infection, cervical cancer and human papillomavirus vaccinesAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 4 2006Michelle GILES Abstract Aims:, Human papillomavirus (HPV) infection is a common sexually transmitted viral infection and is associated with the development of cervical cancer. HPV vaccines are now undergoing phase 3 clinical trials in Australia. It is likely that an HPV vaccine will become licensed for use in the near future. Methods:, Ninety women aged 18,30 years from three different groups (those attending a dysplasia clinic, a local university health service and participants currently involved in a phase 3 HPV vaccine trial) completed a questionnaire assessing their knowledge base regarding HPV infection, cervical cancer, Pap tests and HPV vaccines. Results:, Respondents demonstrated good understanding of the Pap test and interpretation of an abnormal result. Most respondents (89%) had heard of HPV and attributed a number of different clinical symptoms to infection. For women who had not heard of an HPV vaccine, 79% of respondents stated that the most common resource they would use to obtain further information is their general practitioner. Discussion:, Many women do not understand the risk factors for HPV infection, the clinical problems it may cause and the potential long-term complications of infection. Few women have heard of a HPV vaccine, but most women surveyed would approach their general practitioner for more information if one became available. Conclusion:, This study highlights the need for further education regarding HPV infection and the potential long-term complications such as cervical cancer. It also demonstrates that education of general practitioners regarding an HPV vaccine is essential, as this is the most likely resource women will use to obtain further information in the future. [source] Selection on Arctic charr generated by competition from brown troutOIKOS, Issue 3 2003Torbjørn Forseth We experimentally explored population- and individual-level effects on Arctic charr (Salvelinus alpinus) resulting from resource competition with its common European competitor, the brown trout (Salmo trutta). At the population level, we compared performance of the two species in their natural sympatric state with that of Arctic charr in allopatry. At the individual level, we established selection gradients for morphological traits of Arctic charr in allopatric and in sympatric conditions. We found evidence for interspecific competition likely by interference at the population level when comparing differences in average performance between treatments. The growth and feeding rates did not differ significantly between allopatric and sympatric Arctic charr despite lower charr densities (substitutive design) in sympatric enclosures indicating that inter- and intraspecific competition are of similar strength. The two species showed distinct niche segregation in sympatry, and brown trout grew faster than Arctic charr. Arctic charr did not expand their niche in allopatry, indicating that the two species compete to a limited degree for the same resources and that interference may suppress the growth of charr in sympatric enclosures. At the individual level, however, we found directional selection in sympatric enclosures against individual Arctic charr with large head and long fins and against individuals feeding on zoobenthos rather than zooplankton indicating competition for common resources (possibly exploitative) between trout and these charr individuals. In allopatric enclosures these relations were not significant. Diets were correlated to the morphology supporting selection against the benthic-feeding type, i.e. individuals with morphology and feeding behaviour most similar to their competitor, the benthic feeding brown trout. Thus, this study lends support to the hypothesis that Arctic charr have evolved in competition with brown trout, and through ecological character displacement adapted to their present niche. [source] | ||||||||||