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1.
Although lesbians and gays are more visible in the political arena than in the past, there is little published research on their electoral viability. This article helps to fill that void by presenting results of experimental research featuring respondents' reactions to a hypothetical candidate for a non-partisan city council seat. Sex and sexual orientation of the candidates were manipulated so that six categories were tested: a straight woman, a lesbian, a woman rumored to be lesbian, a straight man, a gay man, and a man rumored to be gay. The findings suggest that openly gay and lesbian candidates are seen as less viable than straight candidates or those rumored to be homosexual. Hence, the extent to which a candidate portrays his or her sexual orientation appears to make a difference in the chance to win elective office.  相似文献   

2.
Abstract There is much direct and indirect evidence that in a number of populations the ages of older persons tend to be exaggerated, both when reported in censuses and in records of deaths. This results in overestimated expectations of life at old ages. The bias may be corrected by estimating the expectation of life at age a, e(a), from the mortality rate and growth rate at age a and above, M(a+) and r(a+), using the equation developed in this paper: 1/ê(a) = M(a+) exp (β . r(a+). M(a+)(-α)). For a ?, 65, α = 1.4 and β = 0.0951 have been chosen. The value of the equation rests on the following: since ages of older persons tend to be exaggerated, there may be an age a such that most age transfer occurs above that age, and age transfer across the age is small or cancels, so that reasonably accurate values of M(a+) and r(a +) can be obtained, even though ages are badly reported above a. The analysis of artificial data on Gompertzian stable popultions aged over 50 and actual statistics for some selected populations has suggested that the equation provides quite accurate estimates of e(a). The equation also seems useful in closing life tables, since it provides a value of e(a) for the highest age group.  相似文献   

3.
We directly compare two institutions, a family compact—a parent makes a transfer to her parent in anticipation of a possible future gift from her children—with a pay-as-you-go, public pension system, in a life cycle model with endogenous fertility wherein children are valued both as consumption and investment goods. Absent intragenerational heterogeneity, we show that a benevolent government has no welfare justification for introducing public pensions alongside thriving family compacts since the former is associated with inefficiently low fertility. This result hinges critically on a fiscal externality—the inability of middle age agents to internalize the impact of their fertility decisions on old-age transfers under a public pension system. With homogeneous agents, a strong-enough negative aggregate shock to middle-age incomes destroys all family compacts, and in such a setting, an optimal public pension system cannot enter. This suggests the raison d’être for social security must lie outside of its function as a pension system—specifically its redistributive function which emerges with heterogeneous agents. In a simple modification of our benchmark model—one that allows for idiosyncratic frictions to compact formation such as differences in infertility/mating status—a welfare-enhancing role for a public pension system emerges; such systems may flourish even when family compacts cannot.  相似文献   

4.
Abstract Starting from the definition of a Malthusian population given by Alfred J. Lotka, the author recalls how the concept of stable population is introduced in demography, first as a particular case of stable populations, and secondly as a limit of a demographic evolutionary process in which female age-specific fertility rates and age-specific mortality rates remain constant. Then he defines a new concept: the semi-stable population which is a population with a constant age distribution. He shows that such a population coincides at any point of time with the stable population corresponding to the mortality and the fertility at this point of time. In the remaining part of the paper it is shown how the concept of a stable population can be used for defining a coefficient of inertia which measures the resistance of a population to modification of its course as a consequence of changing fertility and mortality. Some formulae are established to calculate this coefficient first for an arbitrary population, and secondly for a semistable population. In this second case the formula is particularly simple. It appears as a product of three terms: the expectation of life at birth in years, the crude birth rate, and a coefficient depending on the rate of growth and for which a numerical table is easy to establish.  相似文献   

5.
If different groups of people in a low-income society save at different average rates, a program of birth control may affect the aggregate rate of saving by changing the relative shares of income accruing to these groups. A model is outlined in which this process occurs. The only group that saves is profit recipients; peasants and secondary sector employees consume all their income. A decline in fertility leads to a lower demand for food and a lower price of food. This results in a lower money supply price of labor in the secondary sector, and hence greater profits and greater saving. On the other hand, a fertility decline may eventually produce a higher real standard of living among rural workers, hence a higher supply price of secondary sector labor, lower profits and lower saving. These effects are investigated in a simulation of Mexican economic growth with (a) constant high fertility and (b) a declining birth rate such as might occur if a successful national birth control program were instituted. The birth control program results in a higher rate of aggregate saving over the first several decades, and eventually a lower rate of saving once a higher standard of living has been attained.  相似文献   

6.
Demographic research has paid much attention to the impact of childhood conditions on adult mortality. We focus on one of the key aspects of early life conditions, sibling group size, and examine the causal effect of growing up in a large family on mortality. While previous studies have focused on low- or middle-income countries, we examine whether growing up in a large family is a disadvantage in Sweden, a context where most parents have adequate resources, which are complemented by a generous welfare state. We used Swedish register data and frailty models, examining all-cause and cause-specific mortality between the ages of 40 and 74 for the 1938–72 cohorts, and also a quasi-experimental approach that exploited multiple births as a source of exogenous variation in the number of siblings. Overall our results do not indicate that growing up in a large family has a detrimental effect on longevity in Sweden.  相似文献   

7.
Owen  Robert  Ntoko  Alfred  Zhang  Ding  Dong  June 《Social indicators research》2002,60(1-3):179-190
Marketers have traditionally studied diffusionof innovation with a primary focus on theindividual consumer as a unit of analysis, themajor types of findings being characteristicsof adopter categories and opinion leadership. We propose that this perspective is notadequate from a macromarketing perspective, inwhich the goals are to set public policy forsocietal good or to create an environment whichenables the diffusion of an innovation in a waythat no single marketer could do alone. Insetting public policy which can enable (orinhibit) diffusion of innovation for societalgood, a system composed of a mass socialinfrastructure, a competitive infrastructure,and a technical infrastructure should beconsidered.  相似文献   

8.
The quality of life of a society can be considered a function of its complexity which in turn can be indicated by the complexity of its language. Moreover, it is well known that a characterization of a language or of a particular author can be measured statistically. With this in view, this paper surveys and compares a class of linguistic indicators which characterizes languages and authors, presents a uniform review of Zipf's law including extensions and explanations, and presents a new rank-frequency approach which is useful as a linguistic indicator.  相似文献   

9.
BackgroundContinuity models of care are rare in Sweden, despite the evidence of their benefit to women and babies. Previous studies have shown certain factors are associated with a positive birth experience, including continuity of midwifery care.AimThe aim was to investigate women's childbirth experiences in relation to background data, birth outcome and continuity with a known midwife, in a rural area of Sweden.MethodsAn experimental cohort study. Participating women were offered continuity of midwifery care in pregnancy and birth, during selected time periods. Data were collected in mid-pregnancy and two months after birth. The Childbirth Experience Questionnaire was used to determine women's birth experiences.ResultA total of 226 women responded to the follow-up questionnaire. Not living with a partner, fear of giving birth, and a birth preference other than vaginal were associated with a less positive birth experience. Having had a vaginal birth with no epidural, no augmentation and no birth complication all yield a better birth experience. Women who had had a known midwife were more likely to have had a positive birth experience overall, predominantly in the domain Professional support.ConclusionsThe results of this study showed that women who received care from a known midwife in labour were more likely to have a positive birth experience. The results also pointed out the benefits of a less medicalized birth as important for a good birth experience, and that some women may need extra support to avoid a less positive birth experience.  相似文献   

10.
Quorum sensing, a widespread phenomenon in bacteria that is used to coordinate gene expression among local populations, intervenes in the competition between bacteria and the immune system. The domain of attraction of the bacteria-free equilibrium results from a linear matrix inequality optimization with a multivariate polynomial objective under constraints. The Bogdanov-Takens singularity and bifurcation, including a saddle-node bifurcation, a Hopf bifurcation, and a homoclinic bifurcation, are obtained from normal form theory. The normal form of a bifurcation is a simple dynamical system which is equivalent to all systems exhibiting this bifurcation.  相似文献   

11.
Indonesia's family planning program is regarded as a major success.Survey data from 1997 reveal that rates of contraceptive use vary dramatically amongIndonesia's 27 provinces, from a high of 67 percent of ever married women currently using contraceptives in the province of North Sulawesi, to a low of 19 percent current users in East Timor and28 percent in Aceh. This study uses both a quantitative analysis of the 1997 Indonesia Demographic and Health Survey, and a qualitative study carried out in July of 2000 to understand regionalvariation. The study identified a small number of factors that show a clear relation with levels of contraceptive use. Media exposure and education are the strongest and most consistent predictors of levels of contraceptive use, and appear to be the surest strategies for promoting family change. But the study also showed that the process of social change is subjectto culturally and historically specific local factors whose presence and importance is difficult to predict. Our study of regional variation in contraceptive use illustrates the range and complexityof obstacles faced by Indonesia's leaders in attempting to forge a single nation fromsuch a diverse and far-flung population. Although the creation of Indonesia in the space of just half a century is a monumental achievement, the project is clearly not yet complete.  相似文献   

12.
This paper presents a simple method for estimating a birth rate and a level of mortality for an intercensal period. The birth rate is estimated from the intercept of a line fitted to data and the level of mortality from the slope of that line. The formula that is developed is based upon a recent generalization of stable population relations. An estimate of childhood mortality level is an optional but significant piece of additional input. An important by-product of the procedure is an estimate of the true age distribution.  相似文献   

13.
In a forest pest model, young trees are distinguished from old trees. The pest feeds on old trees. The pest grows on a fast scale, the young trees on an intermediate scale, and the old trees on a slow scale. A combination of a singular Hopf bifurcation and a “weak return” mechanism, characterized by a small change in one of the variables, determines the features of the mixed-mode oscillations. Period-doubling and saddle-node bifurcations lead to closed families (called isolas) of periodic solutions in a bifurcation corresponding to a singular Hopf bifurcation.  相似文献   

14.
中国特色的人口转变   总被引:1,自引:0,他引:1  
从人口均衡发展的角度对人口转变理论进行了研究,认为人口转变是由低级人口均衡转变为高级人口均衡的跃迁过程,人口"总量相对静止、结构高位稳定"是最理想的人口发展状态。中国人口转变经历了超前经济发展的"人口转变"和与经济互动发展的"后人口转变"两个阶段,人口转变过程中需跨越"高少儿抚养"和"高老年赡养"的两次陷阱。稳定适度低生育水平和提升人口素质是未来根本任务,从较短期看总和生育率保持在1.8左右,从中长期看总和生育率回归更替水平,是"后人口转变"时期的战略目标,也是促进人口长期均衡发展的必由之路。  相似文献   

15.
A new mortality model based on a mixture distribution function is proposed. We mix a half-normal distribution with a generalization of the skew-normal distribution. As a result, we get a six-parameter distribution function that has a good fit with a wide variety of mortality patterns. This mixture model is fitted to several mortality data schedules and compared with the Siler (five-parameter) and Heligman–Pollard (eight-parameter) models. Our proposal serves as a convenient compromise between the Heligman–Pollard model (which ensures a good fit with data but is often overparameterized) and the Siler model (which is more compact but fails to capture ‘accident humps’).  相似文献   

16.
Although difficulty conceiving a child has long been a major medical and social preoccupation, it has not been considered as a predictor of long-term outcomes in children ultimately conceived. This is consistent with a broader gap in knowledge regarding the consequences of parental health for educational performance in offspring. Here we address that omission, asking how resolved parental infertility relates to children’s academic achievement. In a sample of all Swedish births between 1988 and 1995, we find that involuntary childlessness prior to either a first or a second birth is associated with lower academic achievement (both test scores and GPA) in children at age 16, even if the period of infertility was prior to a sibling’s birth rather than the child’s own. Our results support a conceptualization of infertility as a cumulative physical and social experience with effects extending well beyond the point at which a child is born, and emphasize the need to better understand how specific parental health conditions constrain children’s educational outcomes.  相似文献   

17.
Several studies have demonstrated that stepfamily couples have a higher risk of childbearing than couples in a stable union with the same total number of children. Analysing retrospective data from a nationally representative sample of Swedish adults, we find that the risk of a second or third birth is higher when it is the first or second child in a new union. We also find a faster pace of childbearing after stepfamily formation than after a shared birth. The risk of a second birth (in total) is only a little higher in the first two years after stepfamily formation than in the first two years after a shared birth, and thereafter the risk is lower for stepfamilies. The risk of a third birth (in total) is particularly high early in the stepfamily union and remains higher than that of couples with two shared children for at least five years. The stepfamily difference was lower after than before 1980, when the Swedish government introduced parental leave incentives for short birth intervals.  相似文献   

18.
Coale and Banister argue that in China, elevated sex ratios in retrospective surveys are in part a function of collecting birth histories in a culture in which the definition of a birth may exclude mortality shortly after birth: an infant death in the West may be a stillbirth in east Asia. I present data from a recent sample survey featuring a retrospective pregnancy history. These data reveal that at least in the first pregnancy, from which the preponderance of sample births arise, there is no evidence of elevated female infant mortality or of high numbers of stillbirths, but that reported sex ratios are unusually high. The proportion of stillbirths grows for later pregnancies, but not enough to account for high sex ratios. Retrospective fertility data regarding recall over a recent interval are vexed less by a misunderstanding of what a live birth is than by a “misunderstanding” of what a (reportable) pregnancy is.  相似文献   

19.
This paper considers how a rise in old-age survival probability in a country with a higher old-age dependency ratio (the home country) influences the welfare of a country with a lower old-age dependency ratio (the foreign country). In a dynamically efficient steady-state equilibrium, we show that the old-age survival probability in the home country, when relatively low (high), has a positive (negative) effect on the welfare of the foreign country. We also show that the reform of a social security program in the home country may improve not only domestic welfare but also the welfare of the foreign country.  相似文献   

20.
Currently, a number of contributions in mobility studies are looking for fruitful intersections with other ‘adjacent’ approaches . In this spirit, our theoretical paper argues to study one particular aspect: the intersection of social protection and mobilities. Currently, the provision of social services in the ‘West’ is strongly entrenched within nation-state logics, which assume that clients’ immobility is a precondition of service delivery and that national citizenship is the desirable conditionality of gaining social rights. To overcome such a wide-spread conflation of social security with state security, we introduce the heuristic concept ‘social protection’. It allows social security to be imagined beyond a state-centric perspective and avoids the pitfalls of either a citizenship or a migration approach by taking on a mobility perspective. Thus, for scholars anchored in mobility studies we propose how to develop a social security perspective in a progressive way. For readers from other areas, e.g. citizenship, migration or social policy, we will show how a mobility perspective enriched by a No Border approach can overcome a narrow Western, statist and static perspective on social security. Our goal is to conceptually open up what we call a ‘practical utopia’ research agenda, one that expands our political horizons for future and present socialities.  相似文献   

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