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141.
Jon Anson 《Revue europeenne de demographie》1993,9(1):33-54
Previous analysis has shown that life tables may be distinguished by two orthogonal pieces of information, the level of mortality in the population and the relative shape of the mortality curve. We show that both the regions of England and Wales in 1911, and locality types (county boroughs, other urban, and rural) differ in the shape of their mortality curves. Using data for the administrative counties, we examine the underlying correlates of this differentiation, paying particular attention to the socio-economic structure of the counties as reflected in their wealth, opportunity levels, and degree of urbanisation. 相似文献
142.
This study examines the relationship between occupational status and fertility timing during a period of rapid development in Puerto Rico. Our fundamental hypothesis is that women with higher status occupations face greater opportunity costs than those with less valued jobs and therefore will be more likely to postpone parenthood until later ages than women without such high costs. We test this hypothesis using event history techniques with data from the 1982 Puerto Rico Fertility and Family Planning Assessment, an island-wide survey of women between the ages of 15 and 49. The analysis examines the effects of occupational status on the timing of first births, and finds strong support for the basic hypothesis, especially regarding the post-ponement of teen births. After the teen years, the effects are less pronounced. Overall, it appears that employment opportunities have played an important role in childbearing decisions in Puerto Rico.An earlier version of this paper was presented at the annual meeting of the Population Association of America, Denver, Colorado, 30 April–2 May 1992. 相似文献
143.
144.
盆景艺术风格是盆景艺术家的创作个性在作品中的外在表现 ,它对盆景艺术的发展起着很重要的作用 ,人们对盆景的感性认识直接来源于盆景的风格。大部分盆景方面的书和文章都会涉及到盆景艺术风格的问题 ,但是 ,迄今为止对盆景艺术风格的形成和发展进行过系统研究的人还不是很多。基于对艺术发展规律和中国各种艺术风格盆景发展历史的研究 ,该文详细论述了影响盆景艺术风格形成和发展的内在、外在因素及它们之间的关系 ,并对怎样给我国盆景艺术注入新的活力提出了一些建议 ,对我国盆景艺术的发展和创新起到一定的指导作用 相似文献
145.
Russia’s role in ‘animation’ of the Kyoto Protocol was crucial. Its initial vacillation on ratification was predominantly
due to political bargaining with the EU. Domestic economic rationales [i.e. impacts of emission trading and Joint Implementation
(JI) projects] were important to a much lesser extent and environmental motives did not seem to play any role in the decision.
Since the Protocol entered into force, there have been significant delays in complete establishment of policy implementation
frameworks, which are necessary for Russia to start benefiting from JI and emission trading. Only recently, in 2007, have
GHG inventories and a national registry been established and the responsibilities for implementation of the Protocol and JI
among the government departments have been distributed only to a certain extent. Some constraints hindering JI projects, such
as vague legislation, an unfavourable economic climate, lack of commitment to JI projects, corruption, xenophobia, state and
agency ‘capture’ still remain.
相似文献
146.
Laura Bernardi Andreas Klärner Holger von der Lippe 《Revue europeenne de demographie》2008,24(3):287-313
This article contributes to the ongoing debate on the economic determinants of fertility behavior by addressing the role of
job insecurity in couples’ intentions concerning parenthood and its timing. It starts from the hypothesis that cultural values
moderate individuals’ reactions to job insecurity and the way it is related to family formation. With a systematic thematic
content analysis of a set of semi-structured interviews with childless men and women around the age of 30 in eastern and western
Germany, we are able to show that there are substantial differences in the consequences of job insecurity on intentions to
have a first child. In western Germany, a relatively secure job career is expected to precede family formation, and this sequence
of transitions is rather rigid, whereas in eastern Germany job security and family formation are thought of and practiced
as parallel investments. We suggest that the lack of convergence in family formation patterns between eastern and western
Germany after the unification of the country in 1990 is partially related to different attitudes toward job insecurity in
the two contexts. 相似文献
147.
148.
Michael Kohler 《AStA Advances in Statistical Analysis》2008,92(2):153-178
American options in discrete time can be priced by solving optimal stopping problems. This can be done by computing so-called
continuation values, which we represent as regression functions defined recursively by using the continuation values of the
next time step. We use Monte Carlo to generate data, and then we apply smoothing spline regression estimates to estimate the
continuation values from these data. All parameters of the estimate are chosen data dependent. We present results concerning
consistency and the estimates’ rate of convergence. 相似文献
149.
This paper proposes an experimental test to evaluate the performance of the serial cost sharing rule, originally proposed
by Shenker [Sigmetrics, 241–242 (1990)] and then analyzed by Moulin and Shenker [Econometrica 60, 1009–1037 (1992)]. We report
measures of the performance and efficiency of the serial mechanism by comparing the choices and payoffs attained by the subjects
to the expected equilibrium allocations. Experimental evidence shows that learning is needed for the subjects to converge
to the equilibrium strategy. However, in terms of efficiency, the serial mechanism leads to almost efficient allocations. 相似文献
150.
Terrorist actions are aimed at maximizing harm (health, psychological, economical, and political) through the combined physical impacts of the act and fear. Immediate and effective response to a terrorist act is critical to limit human and environmental harm, effectively restore facility function, and maintain public confidence. Though there have been terrorist attacks in public facilities that we have learned from, overall our experiences in restoration of public facilities following a terrorist attack are limited. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in industrial settings and has many unique technical, economic, social, and political challenges. For example, there may be a great need to quickly restore the facility to full operation and allow public access even though it was not designed for easy or rapid restoration, and critical information is needed for quantitative risk assessment and effective restoration must be anticipated to be incomplete and uncertain. Whereas present planning documents have substantial linearity in their organization, the “adaptive management” paradigm provides a constructive parallel paradigm for restoration of public facilities that anticipates and plans for uncertainty, inefficiencies, and stakeholder participation. Adaptive management grew out of the need to manage and restore natural resources in highly complex and changing environments with limited knowledge about causal relationships and responses to restoration actions. Similarities between natural resource management and restoration of a public facility after a terrorist attack suggest that integration of adaptive management principles explicitly into restoration processes will result in substantially enhanced and flexible responses necessary to meet the uncertainties of potential terrorist attacks. 相似文献