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171.
172.
Governments around the world combat inequality by means of group-specific redistribution. Some pursue redistribution that benefits groups, but also wish to avoid accentuating or even recognizing group distinctions. This poses a dilemma that they try to resolve by adjusting the category system used to target redistribution. There are three types of adjustment: accommodation (the multicultural approach), denial (the ideal-typical liberal solution), and replacement (a compromise). In replacement the targets of redistributive policies are constructed to avoid accentuation or recognition of inconvenient group distinctions, but still allow redistribution that benefits these groups. Replacement is increasingly in demand around the world because the disadvantages of multiculturalism are becoming apparent while denial is hard to sustain in the face of group inequality. The actual effect of replacement is little researched and less understood, however. Does it resolve the dilemma of recognition? Two examples–India and Nigeria–where replacement has been tried ever since the 1950s cast doubt on its viability.  相似文献   
173.
The visible and political gay community has been characterized as an increasingly middle-class, white institution. It is hypothesized that this middle-class nature requires economic and psychosocial resources that are not available to the working class and, thus, may limit the expression of sexual orientation for the working class. An analysis of data from the multicity Urban Men's Health Study supports this hypothesis. Nine of 14 hypothesized effects are statistically significant and indicate that working-class men who are homosexually active are less likely to describe themselves as gay, are more likely to have heterosexual experience, and are less likely to be involved in the gay community. Thus, it is important to incorporate class differences when addressing the social and the political dynamics of sexual orientation.  相似文献   
174.
In this paper we develop a study on several types of parallel genetic algorithms (PGAs). Our motivation is to bring some uniformity to the proposal, comparison, and knowledge exchange among the traditionally opposite kinds of serial and parallel GAs. We comparatively analyze the properties of steady-state, generational, and cellular genetic algorithms. Afterwards, this study is extended to consider a distributed model consisting in a ring of GA islands. The analyzed features are the time complexity, selection pressure, schema processing rates, efficacy in finding an optimum, efficiency, speedup, and resistance to scalability. Besides that, we briefly discuss how the migration policy affects the search. Also, some of the search properties of cellular GAs are investigated. The selected benchmark is a representative subset of problems containing real world difficulties. We often conclude that parallel GAs are numerically better and faster than equivalent sequential GAs. Our aim is to shed some light on the advantages and drawbacks of various sequential and parallel GAs to help researchers using them in the very diverse application fields of the evolutionary computation.  相似文献   
175.
176.
Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.  相似文献   
177.
The extent to which 4‐month attentional regulation during an infant‐mother still‐face situation and 12‐month attachment security during the Strange Situation predicted rates of compliance and noncompliance during a cleanup task at 36 months was examined longitudinally in 70 infant‐mother dyads. Hierarchical multiple regression analyses indicated that infants who showed more attentional regulation during the still‐face situation with mothers later showed a higher rate of committed compliance and a lower rate of situational compliance during cleanup with mothers. Furthermore, lower levels of attentional regulation were later associated with higher rates of assertive behavior, but only for infants in an insecure attachment relationship.  相似文献   
178.
THE ANSWERING MACHINE POSES MANY QUESTIONS FOR TELEPHONE SURVEY RESEARCHERS   总被引:1,自引:0,他引:1  
The proliferation of the telephone answering machine raisesa number of questions about the continued efficiency of thetelephone as a data-gathering mechanism. The most critical ofthese is what effect the use of these machines might have onestablishing contact with potential respondents. If individualsroutinely use these machines to screen calls, then their accessibilityto telephone survey researchers will be restricted. A secondquestion is the degree to which respondents who own answeringmachines and are reachable are likely to participate in a survey.A third question is the extent to which the incidence of theanswering machine as a response disposition might vary by thetime of calling and the respondent's place of residence. Thefindings of this study, based on a nationwide survey, pointto a significant proportion of answering machine owners beingreachable and willing to participate. Furthermore, the answeringmachine appears to be in use more on weekends than on weekdayevenings and in more urbanized areas than in areas with fewerinhabitants.  相似文献   
179.
As a result in part of the way non-profit institutions are defined and treated in the United Nations System of National Accounts (SNA), little is known about the size, scope, financial base and role of this set of institutions at the international level, even though their importance is increasingly being recognised throughout the world. To remedy this significant lack of systematic information on non-profit institutions cross-nationally, the Johns Hopkins Comparative Nonprofit Sector Project has undertaken a major analysis of the economic role of this sector in twelve countries throughout the world, utilising a more meaningful definition of the sector and an approach that is otherwise consistent with the overall thrust of the SNA system. This paper outlines the basis of the more inclusive definition of the non-profit sector embodied in this project, the classification system formulated to structure data-gathering on this more broadly-defined sector and the data assembly strategy developed to build up key estimates of the scale, structure and revenue sources of the non-profit sector in the project countries. The article concludes with a recommendation to incorporate a similar approach to the assembly of data on the non-profit sector into the ongoing SNA system on a regular basis.Professor Lester Salamon is Director of the Institute for Policy Studies and Director of the Comparative Nonprofit Sector Project at the Johns Hopkins University, Baltimore, Maryland, 21218.Helmut Anheier is Research Scientist at the Institute for Policy Studies at the Johns Hopkins University and Assistant Professor of Sociology at Rutgers University, New Brunswick, New Jersey, 08903. He is co-editor ofVoluntas.  相似文献   
180.
The purpose of this paper is to consider the relation between commuting and the settlement structure, with particular attention to rural and nonmetropolitan areas. I examined commuting flows between metropolitan central cities, other metropolitan areas, nonmetropolitan places with more than 10,000 people, those with 2500–10000 people, and other rural areas. Despite the deconcentration of population, industry and trade that was especially marked in the 1970s, commuting in 1980 was predominantly toward larger places in the ruralurban hierarchy, and particularly from rural areas and the other metropolitan category to cities. Overall levels of commuting were high, and most were within either nonmetropolitan or metropolitan areas. Smaller nonmetropolitan places particularly had high proportions of both in- and out-commuters. Differences in commuting flows by gender, socioeconomic status and industry were small, but generally in the directions expected on the basis of prior research. The findings reveal a high degree of work-residence interdependence among settlement units in nonmetropolitan America, with social and economic differences in commuting flows representing an important aspect of community structure.  相似文献   
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