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1.
This paper discusses how fishing communities around the world avoid destructive overfishing through local and largely informal self-management. The paper offers many examples that undermine the widespread assumption that the tragedy of the commons is inevitable without government regulation.  相似文献   

2.
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   

3.
Immigration and internal migration “flight”: A California case study   总被引:2,自引:0,他引:2  
Recent analyses of 1990 census migration data have pointed up disparities in the way immigration and internal migration contributions affect an area's demographic profile. They show that there is little overlap between states with large population gains from internal migration from other parts of the United States and states with large population gains from immigration from abroad. This emerging pattern, along with the fact that immigration and internal migration select on very different demographic characteristics, could lead toward a demographic balkanization of the nation's population. This paper evaluates immigration-induced out-movement from California, based on an analysis of recently released migration data from the 1990 U.S. census. The results presented here suggest that California's out-migration consists of two different migration systems: first, an immigration-induced flight that exports lower income and less-educated Californians, primarily, to the nearby states of Washington, Oregon, Nevada and Arizona. And second, a more conventional migration exchange with the rest of the United States that involves the redistribution of better educated, higher income migrants. It is the former migration system which appears to be most responsive to the low-skilled immigration flows, while the latter should be responsive to more conventional labor market employment characteristics. This implies that, irrespective of changing economic conditions in the state, the continued immigration of low-skilled migrants will lead to more losses of native-born internal migrants to neighboring states and metropolitan areas. However, these migrant streams will not be made up of the best and brightest residents that characterize most conventional migration streams.A longer version of this report with more extensive background statistics isResearch Report 94–306 (Frey, 1994b) available from Publications, Population Studies Center, The University of Michigan, Ann Arbor, MI 48104.  相似文献   

4.
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   

5.
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   

6.
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   

7.
Population projection models that are conceptually simple enough to be called transparent may be used to check the validity of projections generated by black box models whose behavior may be somewhat shrouded in mystery. This paper adopts a multiregional demographic model to illustrate how such a validation procedure might be carried out on state population projections produced by the U.S. Bureau of the Census in 1988.  相似文献   

8.
Estimated demographic effects in proportional hazard models of first birth intervals could reflect time-invariant differences in the risk of a birth, or differences in the timing of a shift in the risk, or both. This paper attempts to distinguish between these possibilities. The procedure is to estimate a more general model than the proportional hazard specification, in which the evolution of the risk of a birth can differ with demographic characteristics. The proportional hazard specification is nested within this more general model. Consequently, the consistency of the data with the risk or the timing interpretation of demographic effects can be tested. The data studied do not lead to a rejection of the proportional hazard specification.Department of Economics, University of Pennsylvania. The initial stage of this research was supported by a National Science Foundation Graduate Fellowship. I have benefited from insightful comments from David Bloom, Andrew Foster, Zvi Griliches, V. Joseph Hotz, Duncan Thomas, anonymous referees, and participants in seminars at Harvard University and the University of Pennsylvania, and in the Economic Demography sessions of the 1988 Population Association of America annual meetings. Any remaining errors are my own.  相似文献   

9.
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   

10.
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   

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.
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   

13.
When applied to monthly age specific data, Granger-Sims causality tests provide a useful technique for identifying the effective lag between business cycles and fertility in the United States. Male and female monthly age specific unemployment rates are used as a proxy for the business cycle, and test results are presented for first and higher order birth rates, as well as total age-specific monthly fertility rates. The period is subdivided (January 1958 – May 1973 and June 1973 – December 1984) in order to identify possible trends. Four results hold in all cases studied, with respect to the relationship between unemployment and fertility. (1) Noncausality is rejected in the direction from unemployment to fertility, and no feedback effect is indicated; thus the relationship is one of simple causality. (2) In the critical decision period from 9–16 months prior to realized fertility rates, the sign of the effect of unemployment on fertility is negative: this holds for both male and female unemployment rates. (3) There appears to have been a shortening of the effective lag between unemployment and fertility, of perhaps 2 – 3 months, between periods 1 (1959 – 1973) and 2 (1973 – 1984). (5) The strength of the (negative) relationship between unemployment and fertility appears to have increased from period 1 to period 2.Presented at the annual meeting of the Population Association of America, Chicago, April 30, 1987. This paper has benefitted from discussions with and comments by Andrew Weiss, Clive Granger, Lee Ohanian and Pietro Balestra, and from comments by two anonymous referees. For help in obtaining previously unpublished data, the authors are grateful to Stephanie Ventura (NCHS), G. P. Goings (BLS) and Paula Schneider (Bureau of the Census). Financial support was provided by the University of Southern California  相似文献   

14.
A recent paper (hereafter referred to as the Paper), Bermingham (2003), presented what appeared to be an analytical review of current situation of declining population growth rates in many parts of the world. The Paper suggested that the increasing growth rates before about 1970 constituted exponential growth, but that the currently declining growth rates were not exponential growth. Hence, the paper asserted that we should not use the terms exponential growth and doubling times in describing the current situation. Many of the suggestions in the paper are contrary to established mathematics. These suggestions are examined here in some detail.  相似文献   

15.
This paper proposes a simple method that analytically links the parameters and , which are not demographically interpretableand measurable in the Brass Relational Gompertz Fertility Model, with demographic measures of median age and interquartile range. We also extend the Brass model that deals only with age-specific fertility to age-parity-specific fertility, first marriage, divorce, remarriage, and leaving the parental home. The method has been successfully tested by fittings to 180 reliable observed demographic schedules in various countries and periods, and to nearly 10,000simulated schedules with various combinations of possible values (including the extremes) of and . Our proposed method that uses median age and interquartile range instead of and as input is useful in the population and family household projections. It releases the traditionalunrealistic assumption in population projections that the curve of the fertility schedule moves to the right or left in a parallel way. Instead, using our proposed method, one can assume that the demographic events would be delayed or advanced, while the curve becomes more spread or more concentrated, or, more specifically, assume that young people delay the events more than the older persons do, or vice versa. Our proposed method is also useful to formulate assumptions on future demographic trends for purposes of policy analysisand planning. It can be used to indirectly estimate demographic schedules when the detailed age-specific data are not currently available, which is useful for developing countries and sub-region studies in developed countries. A crucial point for a successful application of the method is that the standard schedule chosen can capture the general pattern of the demographic process in the population under study.  相似文献   

16.
It is widely believed that work attitudes influence attitudes toward life overall. We investigated a multivariate model of work attitudes and overall life attitudes using survey data from two nationally representative (U.S.) data sets, one cross-sectional and one longitudinal. Including a comprehensive set of control variables, we found only weak support for the attitudes spillover perspective, suggesting that employees often compartmentalize or segregate their work and nonwork lives. We consider theoretical and practical implications of these findings.  相似文献   

17.
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   

18.
Yan  Tan  Yi Qian  Wang 《Population and environment》2004,25(6):613-636
This paper explores the demographic impacts of the implementation of the Grand Development in West China policies and environmental rehabilitation projects in the upper reaches of the Yangtze River. It analyses the interaction between the environmental reconstruction and environment-related migration in this region. The intertwined nature of environmental, ethnic, and poverty problems not only bears negatively upon the alleviation of poverty conducing to the accruement of wealth of the poverty-stricken population, but also hinders the rehabilitation of the environment. It brings forth some opinions regarding improving the capacity of regional sustainable development through environmental migration.  相似文献   

19.
This study evaluates the social and demographic structure of poverty migration during the 1985–90 period based on an analysis of recent census data. Particular attention is given to the roles of two policy-relevant factors that are proposed to be linked to poverty migration. The first of these is the role of immigration from abroad and its effect on the net out-migration of longer-term residents with below-poverty incomes, from States receiving the highest volume of immigrants. Such a response, it is argued, could result from job competition or other economic and social costs associated with immigration. The second involves the poverty population magnet effect associated with State welfare benefits (AFDC and Food Stamp payments) which has come under renewed scrutiny in light of the impending reform of the federal welfare program. The impact of both of these factors on interstate poverty migration is evaluated in a broader context that takes cognizance of other sociodemographic subgroups, and State-level attributes that are known to be relevant in explaining internal migration. This research employs an exceptionally rich data base of aggregate migration flows, specially tabulated from the full migration sample of the 1990 US census (based on the residence 5 years ago question). It also employs an analysis technique, the nested logit model, which identifies separately the push and pull effects of immigration, welfare benefits, and other State attributes on the migration process. Our findings are fairly clear. The high volume of immigration to selected US Statesdoes affect a selective out-migration of the poverty population, which is stronger for whites, Blacks and other non-Asian minorities as well as the least-educated. These results are consistent with arguments that internal migrants are responding to labor market competition from similarly educated immigrants. Moreover, we found that the impact of immigration occurs primarily as a push rather than a reduced pull. In contrast, State welfare benefits exert only minimal effects on the interstate migration of the poverty population—either as pulls or pushes, although some demographic segments of that population are more prone to respond than others. In addition to these findings, our results reveal the strong impact that a State's racial and ethnic composition exerts in both retaining and attracting migrants of like race and ethnic groups. This suggests the potential for a greater cross-state division in the US poverty population, by race and ethnic status.Data Used: 1990 US census tabulations of full migration (residence 5 years ago) sample. Note: Detailed 1990 census statistics on migration of the poverty and nonpoverty populations for individual states can be found in: William H. Frey Immigration and Internal Migration for US States: 1990 Census Findings by Poverty Status and Race, Population Studies CenterResearch Report No. 94-320.This research is supported by the University of Wisconsin Institute for Research on Poverty Small Grants Program and by NICHD grant No. R01 HD29725. The migration data for this paper were prepared at the Population Studies Center, University of Michigan from 1990 US Census files. The authors acknowledge Cathy Sun for computer programming assistance, and Ron Lue-Sang for preparing maps and graphics.  相似文献   

20.
The basic ideas underlying the analysis in this paper are that family size can be viewed as an economic life cycle decision and that there are decision trade-offs among fertility, consumption, and leisure. A micromodel of life cycle choice is developed and embedded in an economic-demographic macromodel. The macromodel is then used in a series of computer experiments to assess the effects on the population and the economy of changes in household preferences for children. The experiments include factual and counterfactual simulations of Canadian historical demographic experience and simulations of alternative future scenarios. The analysis and conclusions have general relevance for countries that have been through a fertility boom-and-bust sequence.We are grateful for the support received from Health and Welfare Canada's Review of Demography and Its Implications for Social and Economic Policy and from the Social Sciences and Humanities Research Council of Canada. We are grateful also to Christine H. Feaver, who carried out the computer-related aspects of the work on which this paper is based.  相似文献   

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