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21.
Population growth,farmland, and the long-run standard of living 总被引:1,自引:0,他引:1
This paper studies the natural-resources element in the theory of population growth over the very long run. In the context of the stock of land and Malthusian crises in earlier times, the model shows how resources have become more available rather than more scarce, even as population and income have increased.The paper sketches a mechanism which, added to the Malthusian system, leads to entirely different conclusions than does the Malthusian system. Using the illustration of food and land, change in knowledge and hence in the stock of resources is made a function of the stock of knowledge and the price of resources. The speed of adjustment depends on the economic and social climate for the development of new knowledge. Population growth first raises food and land prices, which then stimulate the creation of new resources, eventually leading to less scarcity of resources and lower prices than originally prevailed.That is, population growth creates new problems which in the short run constitute additional burdens which, in the longer run, lead to new developments that leave people better off than if the problems had never arisen.This paper benefitted from being presented in earlier draft at a Population Association of America meeting, to the Economic History workshop at the University of Illinois, and to a seminar of the International Union for the Scientific Study of Population in New Delhi. We appreciate valuable comments on earlier drafts from Stanley Engerman, E. L. Jones, William McNeill, and two anonymous referees. Gunter Steinmann acknowledges financial support from the Volkswagen Foundation and a travel grant from Fulbright Commission. 相似文献
22.
Sussman S Galaif ER Newman T Hennesy M Pentz MA Dent CW Stacy AW Moss MA Craig S Simon TR 《Evaluation review》1997,21(1):94-123
Little documentation exists regarding the functioning of formalized adolescent groups as drug abuse prevention agents. Two studies are described that were conducted at high schools whose students are at high risk for drug abuse. Twenty-one schools were randomly assigned to one of three conditions: (a) standard care, (b) classroom drug abuse education only, or (c) classroom plus school-as-community. Results of the first study indicated that the school-as-community component--which involved weekly meetings and periodic events at seven schools--was implemented as planned, drug abused focused, and perceived as productive in discouraging drug abuse. In the second study, staff in the classroom plus school-as-community condition self-reported involvement in the greatest number of community activities across the school year, compared with staff from the other two conditions. These two studies support the feasibility of formalized groups of high-risk youth to promote drug-free events. 相似文献
23.
Sarah E. Turner Thomas I. Nygren William G. Bowen 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》1993,4(1):73-94
An analysis of the field of higher education reveals a surprisingly large number of classification errors within the (US) National Taxonomy of Exempt Entities database. Of the nearly 4,000 non-profit entities coded within the universe of institutions of higher education, we estimate that approximately 60 per cent were incorrectly included (Type II errors). Institutions incorrectly excluded from the higher education universe (Type I errors) represent roughly 10 per cent of the institutions coded correctly. These errors result primarily from assigning codes on the basis of the names of organisations (for example, College Park Towers is classified as a college, when it is in fact a housing complex for senior citizens) and from trying too hard to assign codes in ambiguous situations. The consequences can be significant for the users of these data, and we recommend raising bright warning flags while simultaneously enlisting the help of the entire non-profit sector in improving the classification coding process.The authors are with The Andrew W. Mellon Foundation. In addition to our colleagues on the staff of the Foundation, we wish to thank Helmut Anheier, Ted Bozovich, Harvey Dale, Virginia Hodgkinson, Stephen Noga and Christopher Toppe for helpful suggestions. 相似文献
24.
Simon JL 《Population studies》1980,34(3):476-486
Summary The theory of the low-level equilibrium trap asserts that an increase in income stimulates population growth sufficiently so that the additional people 'eat up' the 'surplus' over subsistence, and hence drive the level of income back to subsistence. Originally the theory referred primarily to mortality, but nowadays its application is to fertility. In the long-run equilibrium context in which the theory is ordinarily presented, the fact that the long-run elasticity of fertility with respect to income is negative in less developed countries fatally contradicts the accepted version of the trap. But to give every chance for trap theory to be meaningful, the paper presents a period-by-period analysis, embodying larger-than-observed positive elasticities during the early years and the logically necessary counterbalancing negative elasticities during the later years. These elasticities are combined with consumption and production figures for various age groups to estimate the effect in each year after the windfall, and altogether. The results show that even under assumptions not charitable to the conclusion of this paper, additional children do not even come close to 'eating up' the increase in income which induced their births, so that the trap theory is falsified. 相似文献
25.
The Abu Sayyaf is an organization which has left a trail of mayhem and murder in the southern Philippines for more than a decade. It has gained international notoriety through several high profile mass kidnappings. This article looks at how the Abu Sayyaf has managed to survive and at times prosper despite the state's efforts to eradicate it. By using organizational analysis the paper demonstrates how the Abu Sayyaf has developed structures and processes which make it such a deadly force. The organization has succeeded in gaining considerable fit with the environment in which it operates. 相似文献
26.
The aim of this article is to foster an awareness of the need for gender‐sensitive research in the context of the methodological and ethical challenges posed by such research. We trace the development of gender sensitivity and masculinity in social work practice and research and connect this to an overview of the issues posed by research on sensitive topics. Reflecting on a research project involving Chinese male sexual abuse survivors, we draw conclusions illustrating and proposing a range of methodological practices and ethical safeguards. We underscore the importance of gender‐sensitivity in performing research on sensitive topics with men in a Chinese community. 相似文献
27.
Quantifying the Establishment Likelihood of Invasive Alien Species Introductions Through Ports with Application to Honeybees in Australia
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The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports. 相似文献
28.
In late 2009 China launched an innovative, voluntary programme that by 2011 had extended pension coverage to 326.4 million people in the rural sector, including contributors and beneficiaries. It requires one contribution per year and provides a flat‐rate benefit and a contributions‐related benefit through a contributory individual account, with a government guarantee that the benefit will continue for life. The programme encourages participation of persons who do not pay income taxes, and thus have no tax incentive to participate, by providing substantial government subsidies. As a further incentive, old‐age benefits are provided to older parents when all their adult children participate in the contributory programme. 相似文献
29.
30.
This study examines the relative importance of soft skills versus hard skills across occupations and its impact on the observed wage gap between Blacks and Whites in the United States. It posits that the Black/White pay gap may vary across occupations that require the use of different types of skills. We classify occupations into hard‐skill intensive versus soft‐skill intensive jobs using the skill content measures of different occupations from the Occupational Information Network (O*Net). We then use data from the National Longitudinal Survey of Youth (NLSY) and Current Population Survey (CPS) to investigate the impact of job skill type on the wage gap. Consistent with our theoretical predictions, we show that this wage gap in white‐collar jobs is smaller for hard‐skills jobs than it is for soft‐skills jobs. Moreover, we demonstrate that, in response to variations in the wage gap across different occupations, Blacks are more likely to self‐select themselves into hard‐skills jobs, ceteris paribus. This shows not only that discrimination against Blacks varies across occupations, but also that such discrimination induces the self‐selection of Blacks into certain occupations. Moreover, this finding highlights the role played by co‐worker/customer discrimination in explaining the racial wage gap in the U.S. labor market. (JEL J15, J31) 相似文献