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991.
992.

Despite the fact that the population of the United States ha shifted from largely rural to largely urban in this century, the commitment to research in recreation, inadequate as it is, has remained in the hinterlands. There is no critical mass of recreation researchers focusing on urban recreation as there now is focused on outdoor recreation. Urban recreation studies have been noncumulative in nature due to the wide range their sponsors, staff, substantive topics, lack of generalizability, and inevitable tensions between practitioners and researchers. Ironically, urban recreational research, and support of it, has diminished in this country at the same time that there has been an increasing concern for such information and knowledge. The future looks bleak insofar as the development of a strong, major, national urban recreation research program is concerned.  相似文献   
993.
Why does the rate of population growth decline in the face of economic growth? We show that growing product variety may induce a permanent reduction in the demand for children and a continuous rise in income and consumption.  相似文献   
994.
Abstract

The involvement construct has received a great deal of attention in recent years. However, the majority of research on this topic has focused on the individual and has ignored spouses’ shared leisure involvement. In addition, little work has been done on involvement in the product‐class context of family vacations. This study examined the underlying dimensions of married couples’ involvement with family vacations and how these dimensions relate to selected personal variables. Factor analysis revealed two underlying dimensions. Stepwise multiple regression revealed that pleasure‐importance was positively related to gender role ideology and education and negatively related to presence of children in the home. A positive relation existed between the second dimension, sign value, and age. The study provides insight into both the nature of the involvement construct and how it might be used in future research.  相似文献   
995.
996.
997.
Abstract

A laboratory‐type experiment was conducted to examine potential information overload causes and solutions. It was found that both information quantity and information complexity are potential causes of information overload. The experiment results also suggested that information overload problems may be reduced through carefully designed information display patterns. When designing survey questionnaires, attention must be given to potential causes of information overload. Methods of presenting information that ameliorate information overload must also be considered. As demonstrated in this study, survey designs can be tested in controlled, laboratory‐type experiments. The results of these experiments can then be used to improve the design of field survey questionnaires.  相似文献   
998.
The precautionary principle, recognized by the European Commission as a 'full-fledged and general principle of international law,' has been advanced as a paradigm for response to potential risks to the environment or health when scientific data are uncertain. But lacking the elements and operational qualities that characterize principles that have proven useful in law, politics, science, and ethics, the precautionary principle lends itself to regulation based on the perception of a threat or fear itself. In the absence of scientific evidence for risk, recent application of the precautionary principle to questions about radiofrequency electromagnetic fields of cellular telephones and cellular telephone base stations has produced wasteful and misguided regulations and questionable advice to the public. The formation of scientific 'fire brigades' is suggested for rapid acquisition of targeted scientific data needed so that precautionary policies on technologically driven issues can be based on quantitative risk assessment.  相似文献   
999.
Population aging has spurred developed countries around the world to reform their PAYG pension systems. In particular, delaying legal retirement ages and reducing the generosity of pension benefits have been widely implemented changes. This paper assesses the potential success of these policies in the case of the Spanish economy, and compares them with the results obtained by the (rather modest) reforms already implemented in 1997 and 2001. This evaluation is accomplished in a heterogeneous-agent dynamic general equilibrium model where individuals can adjust their retirement ages in response to changes to the pension rules. We check the ability of the model to reproduce the basic stylized facts of retirement behavior (particularly the pattern of early retirement induced by minimum pensions). The model is then used to explore the impact of pension reforms. We find that already implemented changes actually increase the implicit liabilities of the system. In contrast, delaying the legal retirement age and extending the averaging period in the pension formula to cover most of the individual's life-cycle can reduce the implicit liabilities substantially. These findings reveal the failure of the Spanish political system to distribute the costs of population aging more evenly across the generations.  相似文献   
1000.
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