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991.
Population and Environment - 相似文献
992.
David E. Simcox 《Population and environment》1992,14(2):159-175
Free trade may well increase immigration from Mexico to the United States before ultimately slowing it down. Rapid population growth, unemployment or underemployment of half the labor force, and vast ethnic and kinship links to the United States have given Mexican migration a stubborn momentum. Increased prosperity from free trade will give many would-be migrants the means to resettle in the U. S. Foreign competition will displace Mexican workers in small farms, state-owned enterprises, and less competitive industries, forcing some to migrate. The noneconomic incentives and expectations driving migration will also remain strong. Mexicans may see free trade as making the border a mere formality or as conferring an entitlement to live in the United States. On the U. S. side, free trade may well deepen the government's traditional complacency about border controls. Over the long-term, however, a successful free trade agreement could reduce immigration by improving Mexico's democracy and the quality of life, diminishing the prospects of mass asylum movements from Mexico, creating a better climate for effective family planning, and luring marginal, immigration-magnet industries from the U. S. to Mexico. In the United States, less- skilled American workers in some industries and regions can expect job displacement and other disruptions from free trade. Particularly vulnerable will be workers in perishable crop agriculture, border retail trade, construction, apparel, and light manufacturing such as furniture, auto parts and glass. Continued heavy immigration of Mexican and other foreign workers into those industries and communities will further impede the adjustment of resident workers by competing for jobs and consuming public resources needed for retraining and job search. To ease the adjustment of displaced workers, the U. S. must make Mexico's cooperation in restraining immigration a condition for free trade. Mexico's cooperation should include enforcement of its own laws against clandestine border crossing; action against alien smugglers, document forgers and transiting illegal aliens from Central America; and curbs on the reentry of aliens deported from the United States. U.S. initiatives that would cushion vulnerable American workers against the added disruption of immigration would be: better identification and screening of applicants for public assistance; tightened enforcement of safety and labor standards in immigrant-impacted firms and provision of legal workers to such firms; protection of public assistance resources through better screening and identification of applicants; and curbs on imports of temporary foreign workers for firms that will now have access to Mexican labor in Mexico. Finally, the United States must consistently press Mexico for higher safety, environmental and labor standards at the workplace to improve the job satisfaction and quality of life of working Mexicans who might otherwise migrate, as well as to narrow Mexico's labor cost advantages over the United States. 相似文献
993.
994.
995.
Gary M. Fournier David W. Rasmussen William J. Serow 《Population research and policy review》1988,7(2):189-199
Discussions about elderly migration and its implications for growth planning tend to neglect the role of economic forces.
Our view is that cost-of-living variations among states give elderly households on fixed incomes an incentive to move that
closely resembles the effects of wage opportunities on workers who migrate. To test this view, we employ a state-by-state
index of cost of living for a retired couple to explore its impact on migration choices of the elderly. The effects of cost
of living on migration are investigated in terms of the probability that an elderly person will move out-of-state during a
five-year period and the probability that a given state will be chosen as destination once a decision has been made to migrate.
The influences of cost of living at both origin and destination are strongly confirmed. 相似文献
996.
This study uses data from the 1990, 1992, 1993 and 1996 panels of the Survey of Income and Program Participation to examine how welfare policies and local economic conditions contribute to women's transitions into and out of female headship and into and out of welfare participation. It also examines whether welfare participation is directly associated with longer spells of headship. The study employs a simultaneous hazards approach that accounts for unobserved heterogeneity in all of its transition models and for the endogeneity of welfare participation in its headship model. The estimation results indicate that welfare participation significantly reduces the chances of leaving female headship. The estimates also reveal that more generous welfare benefits do not directly contribute to headship but rather contribute indirectly to headship by increasing the chances that a mother will enter welfare and consequently remain a single mother for longer. More generous Earned Income Tax Credit benefits are associated with more stable arrangements for both headship and welfare participation. Other measures of welfare policies, including indicators for the adoption of welfare waivers and the implementation of Temporary Assistance for Needy Families programs, are generally not significantly associated with headship or welfare receipt. Better economic opportunities are estimated to increase headship but reduce welfare participation among unmarried mothers. 相似文献
997.
This paper presents a systematic analysis of the culture of natality. In the first section, I present an extended definition of culture informed by cognitive anthropology and evolutionary biology. I argue that culture is an adaptation and a virtual environment with which humans must interact in order to survive and reproduce in a given physical environment. In the second section, I present a qualitative and quantitative analysis of qualitative interview data collected in Oaxaca City, Mexico, on reproductive behavior. The analysis examines evidence of cultural differences and similarities. I conclude by discussing implications for a theory of fertility decline. 相似文献
998.
Much of the academic literature dealing with state and local demography involves the development and evaluation of methods for estimating population. The focus on estimation methods is not surprising because they are used in many states to allocate resources. The quality control in regard to the validity and reliability afforded these methods by the traditional academic peer review process is important because, among other things, it serves to reduce the high potential for conflict that exists when resources are at stake. There are, however, methods being used by state and local demographers that have not been subject to peer review. While not necessarily unsound, these fugitive methods serve to keep the potential for conflict high because of the uncertainty regarding their validity and reliability. This paper examines just such a situation in the form of a case study. It is a discussion of a regression model developed in Nevada following the 2000 census that led to conflict over its use to estimate the population of Clark County, Nevada in 2002. The discussion reveals statistical and methodological shortcomings in this model that lead to an alternative model not subject to these shortcomings. This example illustrates how this type of analysis and discussion can lead to a wider understanding of methods on the part of practitioners through the corrective process of academic peer review. It also suggests that states in which estimates are used to allocate resources would be well-served by subjecting new methods being considered for use to academic peer review before they are adopted. 相似文献
999.
David M. Craig 《Researches on Population Ecology》1986,28(2):173-183
Summary The present research has not identified all of the factors that interact to produce the observed egg cannibalism rates inTribolium. It has, however, shown that some physical and chemical properties of the egg and environment play an important role in determining
cannibalistic activity in a population. Of general interest is the observation that cannibalism is not solely the result of
the biological characteristics of the cannibal. While it is generally acknowledged that the quality and quantity of food may
influence the intensity of cannibalism, it is not generally recognized that the environment can affect cannibalism in as complex
a manner as is suggested by the current research. That two such closely related species, and even two life-stages of the same
species, may respond so differently to the same environmental cues is impressive. Predicting the intensity and hence the importance
of cannibalism in natural populations may be difficult without detailed empirical studies. 相似文献
1000.
Gary M. Fournier David W. Rasmussen William J. Serow 《Population research and policy review》1988,7(3):189-199
Discussions about elderly migration and its implications for growth planning tend to neglect the role of economic forces.
Our view is that cost-of-living variations among states give elderly households on fixed incomes an incentive to move that
closely resembles the effects of wage opportunities on workers who migrate. To test this view, we employ a state-by-state
index of cost of living for a retired couple to explore its impact on migration choices of the elderly. The effects of cost
of living on migration are investigated in terms of the probability that an elderly person will move out-of-state during a
five-year period and the probability that a given state will be chosen as destination once a decision has been made to migrate.
The influences of cost of living at both origin and destination are strongly confirmed. 相似文献