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991.
We explore how natural selection acts upon genes for cooperation, altruism and selfishness in an prisoner's dilemma played by family members. A key parameter determining behavior is that parents and children have different expectations of future offspring. Examining asexual and sexually reproducing populations we show that which strategy of cooperation and defection proves be stable depends on the relative reproduction potential of the players and what proportion of the population is young. "Rotten kids" with altruistic parents can be a stable outcome where reproductive success is the goal, and natural selection may lead individuals to care about their unborn progeny. (JEL D10, H31)  相似文献   
992.
Existing analyses of the effects of fiscal policy in general equilibrium models have typically been conducted under the assumption that the long-run supply of capital is perfectly elastic at a fixed rate of time preference. These analyses have shown that the long-run response of the capital stock to changes in fiscal policy is crucial to generating the potential for “multiplier” effects in these models. In this paper we ask, what are the implications of relaxing the assumption of perfectly elastic capital supply for the analysis of fiscal policy? We show that with less than perfectly elastic capital supply, the potential for multipliers is actually enhanced. (JEL E62, D90)  相似文献   
993.
Using the 1980 and 1990 Public Use Microdata Samples, we find that labor market outcomes associated with English proficiency vary with respect to gender. For example, a synthetic cohort analysis provides evidence of gender-related differences in Hispanic workers' English skill acquisition. Moreover, we observe that Hispanic women face a lower English deficiency earnings penalty that rises more sharply with education than the penalty obtained by their otherwise similar male peers. Finally, English fluency appears to serve as a stronger occupational sorting mechanism for women than men. ( JEL J3, J1)  相似文献   
994.
I regard electronic media technologies as framing devices for how viewers perceive issues associated with illegal drugs. Controllers of electronic media technologies produce and disseminate images of illegal drugs and users of such drugs to which viewers respond. People who control the images of electronic media production create an evocative telepresence, or a visual context that relies on appeals to authority and emotion. However, viewers do not merely respond to images of illegal drugs; rather, they actively interpret such images and draw their own conclusions. To demonstrate the complex relationship between electronic stimuli and viewer responses, I report on a classroom experiment comparing those who saw and heard a heroin user with those who only heard this user. I also report findings from student perceptions of and reactions to four drug films. Results of the experiment and the readings of films indicate that viewers, especially those who can see and hear electronic displays, are sophisticated consumers who respond to immediate stimuli while making reference to distal stimuli. In the main, I contend that electronic images of illegal drugs and users in an evocative telepresence are powerful stimuli, but they do not cause viewer perceptions.  相似文献   
995.
The Effects of Diversity on Small Work Group Processes and Performance   总被引:2,自引:0,他引:2  
Diversity is an increasingly important factor inorganizational life as organizations worldwide becomemore diverse in terms of the gender, race, ethnicity,age, national origin, and other personal characteristics of their members. The exact impact ofwithin-group diversity on small group processes andperformance is unclear. Sometimes the effect ofdiversity seems positive, at other times negative, andin other situations, there seems to be no effect at all.In this article, we suggest that these types of findingsmight be explained by using agroup-development model to examine theimpact of diversity on group processes and performance. Our modeluses concepts from Jackson et al.'s (1995), Milliken andMartins' (1996), and other models, as well as our ownconcepts, to show how diversity affects group development and performance. Among the conceptsincluded in the model are readily detectable personalattributes, underlying personal attributes, cognitiveparadigm dissimilarity, cognitive costs and rewards, diversity management skills, group behavioralintegration, and cognitive performance resources. In thepages that follow, we will explain each of thecomponents of the model and suggest specific hypotheses generated from the model.  相似文献   
996.
In 1992 a record 14 women sought statewide office by running"as women" and as representatives of women. In this articlewe examine whether their appeals led to widespread vot ing onthe basis of gender identity. We find evidence that the sexof the voter is significantly related to voting for female candidatesin eight of 13 states, and among partisans of both parties aswell as Independents. Further, we find that these effects areamplified by Democratic female candidates who are rated as mostfeminist, and that this is especially the case for those withno partisan attachments.  相似文献   
997.
USAID has assisted the Ghanian Ministry of Health since 1991 to boost family planning services under the Ghana Family Planning and Health Project by providing supplies and information and increasing the effectiveness of HIV/AIDS prevention and control. The sustainability of the health system is endangered by favoring capital expenditures in lieu of continuous expenditures; the lack of linkage between project activities and regular activities; the centralization of resource flow; and too ambitious targeting. Capital outlays provided by USAID featured in the construction of four public health laboratories, but their operation also requires continuous financing amounting to about 10% of the whole investment. The latter is the responsibility of the government, although the details of these recurrent costs were not detailed at the outset and providing these funds for continuous operation may impair the operation of other systems. The resource constraints could be alleviated by an effective cost-recovery system or by the general improvement of the economy. The lack of linkage between project and regular activities is serious at regional and district levels. The centralization of resource flow means that most resources are kept for headquarter level activities, thus other activities suffer and the health sector becomes excessively reliant on donor support. Too ambitious planning stems from pressure on donors and hastily implemented projects result in duplication and waste. Closer consultation with the parties involved would improve the situation. The rivalry of technical and policy groups has contributed to past deficiencies. Double funding for the same activity has also occurred further increasing the dependence on donor funding. By concentration on people and systems sustainability would be enhanced, while cost recovery would help the operation of the laboratories. The Health Education Unit (HEU) recognized the importance of IEC and obtained financing for such activities.  相似文献   
998.
SupposeL(X) is the law of a positive random variableX, andZ is positive and independent ofX. Admissible solution pairs (L(X),L(Z)) are sought for the in-law equation $\hat X \cong X o Z$ °Z, where $L\left( {\hat X} \right)$ is a weighted law constructed fromL(X), and ° is a binary operation which in some sense is increasing. The class of weights includes length biasing of arbitrary order. When ° is addition and the weighting is ordinary length biasing, the class of admissibleL(X) comprises the positive infinitely divisible laws. Examples are given subsuming all known specific cases. Some extensions for general order of length-biasing are discussed.  相似文献   
999.
This paper addresses the questions of citizenship in socially diverse polities. Such issues are presently not dealt with adequately because social scientists, parliamentarians and policy makers do not have an informed view which is relevant for the governance of stable democratic systems which embody cultural diversities. The role of social policy systems in ensuring equity in the delivery of services is important in ensuring the citizenship rights of all groups in society.

At the present time economic policies have created a culture of winners and losers which makes the efforts of schools more difficult.

The schools and the educational systems face the challenge of creating a common and shared values orientation on the diversities in the polity. Such communities also present the schools with immense possibilities, if teacher education, school policies and practice, curriculum and classroom organisation can be optimised. Such measures may help obviate the school exclusion of specific groups.  相似文献   

1000.
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