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1.
The imminent decline of populations in Europe, Japan and South Korea has generated widespread apprehension, largely because of fears that there will not be enough working age people to support the elderly. The UN Population Division has seemed to endorse those fears by an analysis of the levels of immigration needed to provide a constant number or ratio of workers, and by writing of the need for a solution to population decline. On the other hand, smaller populations would be environmentally advantageous in those countries. They must return to replacement level fertility or risk replacement by other populations, but they would benefit if they reached stationarity at a smaller population level. The transition is manageable if a higher proportion of working age people go to work. Right now, though dependency ratios are supposedly highly favorable, most of those countries are plagued by high unemployment levels.  相似文献   

2.
This paper analyses the interrelation between the transport system and measures of resource consumption such as material and energy consumption over a 60-year period (1937–1997) in the UK. Non-motorized transport and time consumption for mobility are estimated in addition to conventional measures of transport. During the period analyzed, the UK population grew by 20% while transport of goods and persons increased more than threefold and material and energy consumption almost doubled. The transport intensity of domestic material input (DMI) doubled to 300 ton-kilometers (tkm) per ton of DMI while the transport intensity of domestic energy consumption (DEC) doubled to 20 tkm per gigajoule (GJ) of DEC. Thus, while the material and energy intensity of GDP declined significantly, a well-established trend in many advanced countries, the transport intensity of materials and energy consumption rose. These findings suggest a close link between transport, economic development, and long-term structural transformations. In the case of personal transport, a rebound effect was also observed: whereas the average speed of transport has greatly increased, the average number of hours per day devoted to personal transport has not declined.  相似文献   

3.
We use data from the National Longitudinal Survey of Youth to examine the relationships between maternity leave coverage and U.S. womens post-birth leave taking and employment decisions from 1988 to 1996. We find that women who were employed before birth are working much more quickly post-birth than women who were not. We also find that, among mothers who were employed pre-birth, those in jobs that provided leave coverage are more likely to take a leave of up to 12 weeks, but return more quickly after 12 weeks. Our results suggest that maternity leave coverage is related to leave taking, as well as the length of time that a new mother stays home after a birth.All correspondence to: Jane Waldfogel. Funding for this project was provided by the National Institute of Child Health and Human Development and the William T. Grant Foundation. We are grateful to the editor and two anonymous referees for helpful comments. Responsible editor: Daniel S. Hamermesh.  相似文献   

4.
This paper presents a typology and qualitative model of causation for use in assessing the relative contributions of population growth to problems of pollution, lost biodiversity, and natural resource depletion. Population growth is placed in context as one of eight key driving forces that shape environmental quality today. It is treated primarily as an impact amplifier, along with technology. Root causes are traced to paradigmatic beliefs—especially anthropocentrism and contempocentrism—which find expression in unsustainable consumption patterns and designs of political economy.  相似文献   

5.
The crucial challenge for integrated analyses of socioeconomic systems is keeping coherence in their multidimensional representation. Our approach describes the hierarchical structure of socioeconomic systems using the profile of allocation of human activity over a set of compartments defined at different hierarchical levels (e.g., whole countries, economic sectors, individual households). Compartments are characterized in terms of intensive variables (intensity of both exosomatic energy flows and added value flows per unit of human activity) and the extensive variable Total Human Activity population. In this way, relations of congruence across hierarchical levels can be used to link non-equivalent analyses. That is, changes in demographic variables, economic variables, technical coefficients, indices of environmental loading, institutional settings, and social aspirations are no longer independent of each-other even if described within different scientific disciplines.  相似文献   

6.
This study presents a detailed look at the immigration and internal migration dynamics of child poverty for US States based on the 1990 US census. It assesses the impact of two policy-relevant factors on the migration of poor children across States: (1) the role of high immigration levels as a potential push for native-born and longer-term resident poor children whose parents may be reacting to the economic competition or social costs in high immigration States; and (2) the role of State AFDC benefits as a potential pull for poor children who migrate with their parents to States with higher benefit levels. The results make plain that the interstate migration patterns of poverty children differ from those of nonpoverty children, especially among whites and blacks. Female-headed households show different inter-state migration patterns than those in married-couple households. However, a multivariate analysis which includes standard state-level economic attributes provides more support for an immigration push than for a welfare magnet pull in affecting the inter-state migration of poor children. The findings also show a demographic displacement of poor children occurring in high immigration States where the net out-migration of poor children is more than compensated by larger numbers of new immigrant children in poor families with different demographic attributes. Because of these migration dynamics, the demographic profile of the child poverty population will differ across States, suggesting the need for different strategies toward reducing child poverty at the State level.  相似文献   

7.
The effects of labour supply growth on the welfare of preexisting destination and non-emigrating source populations are analysed. This growth occurs in open economies where free trade in capital goods is possible. Traditional small economy arguments for population growth rely on the existence of priced though internationally immobile factors. When all factors are freely-traded and population grows naturally the case rests either on market distortions or common property within families. In an integrated world labour growth can lead to capital flight and increasing wage differentials. With international interactions, immigration increases preexisting welfare in destination countries but generally (not always) reduces it for non-emigrants in source countries. Immigration provides efficiency gains to all originally resident in source countries. Natural population growth anywhere promotes efficiency gains everywhere.  相似文献   

8.
Exponential Growth and Doubling Times: Use of these popular population buzzwords of the last half of the twentieth century was fully justified by the growth rates of that period. However, those growth rates have now all but disappeared and so have the underlying reasons that those buzzwords made sense. Misuse of such expressions today costs credibility. Though the world's population growth certainly does remain vigorous and robust, creating many reasons for concern, nowhere today is growth projected as exponential. The essence of exponential growth is analyzed and distinguished from exponential curves, and non-exponential growth. Several types of current population growth are recognized, none being exponential. In periods of non-exponential growth, a Doubling Time calculated from a single annual growth rate is grossly erroneous and often absurd. Other standard measures of growth are needed. United Nations projections should include figures for percentage growth by 2025 and 2050.  相似文献   

9.
This paper presents an application of an innovative methodological tool for the integrated assessment of farming systems (Multi-Objective Multiple-Scale Integrated Representation). It describes the effect of rural development in parallel on economic and ecological reading at different levels: household, village, and the commune comprising 3 villages. Socio-economic and environmental indicators are organized into integrated packages across scales. This is an ex-post facto analysis of a program of rural development implemented in the Central Vietnamese uplands in 1995 by the central government with the collaboration of FAO. We conclude that two classic problems can only be faced by using an integrated analysis across levels: Large scale generalizations can miss important location-specific characteristics, and exclusive focus on location specific issues carries the risk of loosing the big picture.  相似文献   

10.
In a recent contribution to this Journal Anjomani and Hariri present an interesting study of United States interstate migration which explicitly incorporates so-called flow diversion and flow creation effects. Their discussion and evaluation of the model, however, are marred by several factors. This paper contrasts the roles of migrant stock and lagged migration in migration analysis and then addresses (a) the problems encountered when the family-friends effect is proxied with measures of lagged migrant flows, (b) the problem of using a two-period lagged value of earlier migrant flow as an explanatory variable, and (c) this paper suggests an alternative method of correcting the Anjomani-Hariri model's problems with multicollinearity.The author is grateful to Walter J. Wadycki and to David A. Macpherson for helpful comments and suggestions. The author, of course, bears full responsibility for all errors that remain. This research benefited from a grant from the Miami University Committee on Faculty Research.  相似文献   

11.
Using Current Population Survey data, Vital and Health Statistics data, photoperiod data and temperature data, this article attempts to provide an interdisciplinary explanation of monthly (N = 243) variation in the dependent variable representing the birth rate (the rate of conceptions that become live births) for white women 20–24 years of age. Among the selected explanatory variables, four were found to play significant roles in accounting for the variation of the birth rate. They were rates of female absence from the labor market (nonparticipation plus unemployment), male employment rates, length-of-night variations and the days in the month of conception. Rainwater's concept of validating activities (1974) and recent quality of life research regarding domains serve as a basis for development of the concepts compensatory validation and contextual compatibility. Research and policy implications are discussed.  相似文献   

12.
During the 1990s, 23 states implemented family cap policies as a means to reduce the incidence of out-of-wedlock births among welfare recipients. Using Current Population Survey data from 1989 to 1999, we examine the impact of family cap policies on the birth rates of single, less-educated women with children. We use the first five states that were granted waivers from the Department of Health and Human Services to implement family caps as natural experiments. Specifically, we compare trends in out-of-wedlock birth rates in Arkansas, Georgia, Indiana, New Jersey and Virginia to trends in states that did not implement family caps or any other waivers prior to the Personal Responsibility and Work Opportunity Reconciliation Act. We employ several techniques to increase the credibility of results from our natural experiment, such as the inclusion of multiple comparison groups, controls for differential time trends, and difference-in-difference-in-differences estimators. Our regression estimates generally do not provide evidence that family cap policies reduce the incidence of out-of-wedlock births among single, less-educated women with children.  相似文献   

13.
The related terms, sustainable and sustainability, have become popular and are used to describe a wide variety of activities which are generally ecologically laudable. At the same time, the term compromise is heard more frequently because the needs of the environment often are in conflict with the needs of humans. A brief examination of the question of compromise shows that a series of ten compromises, each of which saves 70% of the remaining environment, results in the saving of only 3% of the environment. Judging from the ways in which the terms sustainable and sustainability are used, their definitions are not very precise, especially when compromises are involved. An attempt is made here to give firm definition to these terms and to translate the definition into a series of laws and hypotheses which, it is hoped, will clarify the implications of their use. These are followed by a series of observations and predictions that relate to sustainability.  相似文献   

14.
This paper explores the role of mortality in the long transition from Malthusian stagnation to sustained economic growth. An endogenous child mortality rate that varies inversely with parents standard of living is added to the framework in Galor and Weil (AER 2000). In our version of the model, the transition from stagnation to growth, triggered by an exogenous shock to technology, comprises a mortality revolution succeeded by a demographic transition.This paper has benefitted from discussions with and suggestions made by KarlGunnar Persson, Christian Schultz, and, particularly, Christian Groth at the University of Copenhagen. I gratefully acknowledge the insightful criticisms of two anonymous referees, and I thank Paula Madsen for English proof-reading. Responsible editor: Alessandro Cigno.  相似文献   

15.
The predominant reform tradition of centralizing suburban government to deal with problems of inequality in the distribution of local services has been attacked recently by a new school of thought often labelled New Political Economists. This school believes that the existing structure of local government can maximize citizen choice by allowing citizens to shop around between the level and mix of public goods and services offered by alternate communities. The term polycentricity has been coined to describe this situation. Critics of polycentricity believe that the resulting quasi-market would be unfair to low and moderate income suburbanites. This paper examines the actual extent of choice in service levels available to different income groups located in the suburban ring of six metropolitan areas. The extent of inequality in choice between different income groups is measured and the implications of these findings for the conflict between polycentric and centralizing reformers is discussed.The research reported in this paper was funded by the National Science Foundation, Grant Number SOC7705600  相似文献   

16.
Just as we have a turn around manager to save a failing business organization, so it is held, we need a turn around perspective to retrieve the Earth from being in a deficit position. Hence the paradoxical emphasis upon the Earth as the business of the future. Two important distinctions are offered which together provide a new frame of reference for bonding the human and the Earth. The initiating event for the first distinction was a business conference whose purpose was to explore the emerging domain of ego energy. In a parallel way, it is proposed we explore the yet to be discovered domain of eco energy. With eco energy we open our narrowed human window to cosmic perception. With cosmic perception, the energy of the universe can flow through us. The second distinction is between looking at and seeing. Looking at refers to treating our world as a collection of objects. As a collection of objects the Earth can be processed as a series of business transactions. With seeing we relate to our world as a communion of subjects. Such seeing offers transforming power for the human and the Earth to engage in the dialogue of powerful listening and speaking on both individual and planetary scale. These two sets of distinctions are sounded like echo chambers against ten ecologically guiding statements. These ten guiding statements become a reality-testing, experiential framework. Such a turn around perspective offers a different vision to be operationalized in our individual, community, and business lives. Then we can see clearly and respond with eco energy to the Earth, the business of the future!  相似文献   

17.
This article analyzes differences in estimates of the number of illegal aliens in the United States. Although smaller than differences among estimates made by some of the earlier studies, estimates constructed in the past decade often differ by several million. An examination of the problems involved in making these estimates produced four likely sources of the discrepancies. The four sources of disagreement are discussed, followed by suggestions for improving the reliability of the estimates. Some consequences for immigration law reform are also addressed.  相似文献   

18.
In the extensive litigation over school board liability for segregated schools, a great deal of attention has been focused on changes in school attendance areas. Evidence presented in several trials suggested that school boards have gerrymandered boundaries to keep some schools black and others white. Even though both district and appeal courts have found violations in attendance zone changes, there has been little other than anecodotal evidence to support these findings. In many cases the areas with the most changes in attendance boundaries are also the areas of rapid racial transition, but correlation does not necessarily mean causation. This case study examines boundary changes in Topeka and suggests that racial change in schools is more directly attributable to demographic shifts than to attendance boundary changes.  相似文献   

19.
Managed growth is a politically popular rallying point which offends no faction by insisting upon nonnegotiable limits. Subscribers to this philosophy focus upon short-run accommodations to growth which apparently mitigate its physical consequences. Managed growthers react to longterm numerical projections with rejection, if not outright hostility. They may be more amenable to quality-of-life rationales for population limitation evolving from the biophilia hypothesis and ecopsychology. These theories claim that our species needs to exist in proximity to untrammelled wilderness and a natural environment for psychic health and creativity.  相似文献   

20.
This study forms part of a general programme of research aimed at evaluating the quality of life in Rome. In particular, we have wished to analyse the way in which housing quality, measured with indicators of housing structure and utilization, intersects with the quality of urban livability, measured here only with indicators of social background, homogeneity and hardship referring to subjects living in the individual segments of the city. Groups of territorial areas, homogeneous by housing typology, were identified using multivariate data analysis and it was thus shown how particular typologies of household respond to this supply. From this emerged a particular model of development of the city in concentric bands, within which the originally differentiated households have tended over time to assume homogeneous characteristics.  相似文献   

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