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1.
The Happiness Scale Interval Study deals with survey questions on happiness, using verbal response options, such as ‘very happy’ and ‘pretty happy’. The aim is to estimate what degrees of happiness are denoted by such terms in different questions and languages. These degrees are expressed in numerical values on a continuous [0,10] scale, which are then used to compute ‘transformed’ means and standard deviations. Transforming scores on different questions to the same scale allows to broadening the World Database of Happiness considerably. The central purpose of the Happiness Scale Interval Study is to identify the happiness values at which respondents change their judgment from e.g. ‘very happy’ to ‘pretty happy’ or the reverse. This paper deals with the methodological/statistical aspects of this approach. The central question is always how to convert the frequencies at which the different possible responses to the same question given by a sample into information on the happiness distribution in the relevant population. The primary (cl)aim of this approach is to achieve this in a (more) valid way. To this end, a model is introduced that allows for dealing with happiness as a latent continuous random variable, in spite of the fact that it is measured as a discrete one. The [0,10] scale is partitioned in as many contiguous parts as the number of possible ratings in the primary scale sums up to. Any subject with a (self-perceived) happiness in the same subinterval is assumed to select the same response. For the probability density function of this happiness random variable, two options are discussed. The first one postulates a uniform distribution within each of the different subintervals of the [0,10] scale. On the basis of these results, the mean value and variance of the complete distribution can be estimated. The method is described, including the precision of the estimates obtained in this way. The second option assumes the happiness distribution to be described as a beta distribution on the interval [0,10] with two shape parameters (α and β). From their estimates on the basis of the primary information, the mean value and the variance of the happiness distribution in the population can be estimated. An illustration is given in which the method is applied to existing measurement results of 20 surveys in The Netherlands in the period 1990–2008. The results clarify our recommendation to apply the model with a uniform distribution within each of the category intervals, in spite of a better validity of the alternative on the basis of a beta distribution. The reason is that the recommended model allows to construct a confidence interval for the true but unknown population happiness distribution. The paper ends with a listing of actual and potential merits of this approach, which has been described here for verbal happiness questions, but which is also applicable to phenomena which are measured along similar lines.  相似文献   

2.
Summary Theoretical and analytical problems of the dynamics of distribution and abundance in animal communities were examined. In many communities, species with low abundance and of limited spatial occurrence (i.e., rare species) typically form a conspicuous peak when a frequency distribution of the number of species is constructed with respect to the proportion of sites occupied within an area of distribution. Models of distribution dynamics, including a new model proposed here, were compared with a range of animal community data using a new procedure to assess single- and bi-modal patterns in frequency distributions of spatial occurrence. Data reveal that single-modality with an excess of rare species occurs more frequently than bimodality. Even when bimodality is detected, the mode representing wide-spread species is in the majority of cases smaller than that for rare species. Thus, a new model in which the rate of local extinctions is assumed to be negatively related to patch occupancy (or population abundance) is in better agreement with observed data than earlier models. Some problems of analysis, in particular model assumptions and testing, are discussed.  相似文献   

3.
This article decomposes total population momentum into two constituent and multiplicative parts: “nonstable” momentum and “stable” momentum. Nonstable momentum depends on deviations between a population’s current age distribution and its implied stable age distribution. Stable momentum is a function of deviations between a population’s implied stable and stationary age distributions. In general, the factorization of total momentum into the product of nonstable and stable momentum is a very good approximation. The factorization is exact, however, when the current age distribution is stable or when observed fertility is already at replacement. We provide numerical illustrations by calculating nonstable, stable, and total momentum for 176 countries, the world, and its major regions. In short, the article brings together disparate strands of the population momentum literature and shows how the various kinds of momentum fit together into a single unifying framework.  相似文献   

4.
The impact of population structure on economic growth has been studied in recent decades using different methods to estimate the so‐called demographic dividend. Besides, education has been pointed out as a key factor in economic growth. We propose a decomposition of the demographic dividend, into age and education effects. We illustrate the potentialities of the method, deriving an application to Mexico and Spain over the period 1970‐2100. To that end, we estimate the National Transfer Accounts age profiles by schooling level and apply them to recently available population projections stratified by education level. Our results confirm the role of population age structure in the demographic dividend, but also reveal that education attainment can be even more crucial. Moreover, we find that how both age and education effects finally impact on economic growth depends to a great extent on the specific consumption and labor income age profiles in each country.  相似文献   

5.
Our analysis of changing birth interval distributions over the course of a fertility transition from natural to controlled fertility has examined three closely related propositions. First, within both natural fertility populations (identified at the aggregate level) and cohorts following the onset of fertility limitation, we hypothesized that substantial groups of women with long birth intervals across the individually specified childbearing careers could be identified. That is, even during periods when fertility behavior at the aggregate level is consistent with a natural fertility regime, birth intervals at all parities are inversely related to completed family size. Our tabular analysis enables us to conclude that birth spacing patterns are parity dependent; there is stability in CEB-parity specific mean and birth interval variance over the entire transition. Our evidence does not suggest that the early group of women limiting and spacing births was marked by infecundity. Secondly, the transition appears to be associated with an increasingly larger proportion of women shifting to the same spacing schedules associated with smaller families in earlier cohorts. Thirdly, variations in birth spacing by age of marriage indicate that changes in birth intervals over time are at least indirectly associated with age of marriage, indicating an additional compositional effect. The evidence we have presented on spacing behavior does not negate the argument that parity-dependent stopping behavior was a powerful factor in the fertility transition. Our data also provide evidence of attempts to truncate childbearing. Specifically, the smaller the completed family size, the longer the ultimate birth interval; and ultimate birth intervals increase across cohorts controlling CEB and parity. But spacing appears to represent an additional strategy of fertility limitation. Thus, it may be necessary to distinguish spacing and stopping behavior if one wishes to clarify behavioral patterns within a population (Edlefsen, 1981; Friedlander et al., 1980; Rodriguez and Hobcraft, 1980). Because fertility transition theories imply increased attempts to limit family sizes, it is important to examine differential behavior within subgroups achieving different family sizes. It is this level of analysis which we have attempted to achieve in utilizing parity-specific birth intervals controlled by children ever born.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

6.
Summary I propose a new method for anlysing predatorprey interactive systems in discontinuous environments. The basic index used here is a generalized version ofLloyd's (1967) “interspecies mean crowding”, which is defined as the number of individuals of one species existing in a given patch per that of the other species in either the same or different patches at either the same or different times. Four indices are derived from different combinations of the numbers of the prey and the predator in habitat patches. Then, the correlation coefficients between the numbers of individuals in patches in both different locations and times are derived by modifying the above new indices. Using this technique, dynamical changes of the joint distributions of the numbers of predators and prey which reflect variation in local conditions, can readily be described. As an example, this method was applied to an analysis of the outcomes of a multi-patch version of theLotka-Volterra model of predator-prey interactions.  相似文献   

7.
Fertility across and within countries is influenced by a number of socio-economic and cultural factors, including ethnicity and potentially religion. However, apart from census data, little information is available, at least in the UK, to estimate fertility rates and thus fertility trends by ethnic and religious groups between censuses. Previously, the Labour Force Survey (LFS) has been exploited to produce national total fertility rates (TFR) by ethnic groups up to 2001 using the reverse-survival Own-Children Method (OCM). Here the LFS–OCM is assessed and refined to improve accuracy and tested against official statistics. The LFS–OCM is compared with results obtained using more straightforward techniques based on Child-Woman Ratios using the same LFS data, and differences are discussed. The refined method is applied to produce recent fertility profiles by ethnic groups, including trends in the TFR and age-specific fertility rates, showing significant and decreasing differences between groups. Furthermore, the method allows us to reliably investigate TFR within one ethnic group by other criteria, as illustrated by differences in the TFR by religious affiliation of Indian women.  相似文献   

8.
This paper describes the changing spatial distribution and concentration of Chinese and Vietnamese communities in Australia over the two past decades. The research analyses data of individuals (i) born in the People’s Republic of China or Vietnam, (ii) of Chinese or Vietnamese ancestry, and (iii) who spoke Chinese or Vietnamese languages at home. Basic demographic and economic factors at the SLA level are considered to provide an initial discussion of meso-level factors which may have contributed to changes in Chinese-and Vietnamese-Australian distributions and concentrations since 1986. As expected, from field observations, the data reveal a contrasting picture of the spatial distribution and concentration of the Chinese- and Vietnamese-Australian communities, and indicate that although a few areas of high Vietnamese spatial concentration have persisted into 2006, and a few areas of high’ Chinese spatial concentration have developed since 1986, overall there is an increasing dispersion of both communities into the broader Australian community.  相似文献   

9.
Better childhood nutrition is associated with earlier physical maturation during adolescence and increased schooling attainment. However, as earlier onset of puberty and increased schooling can have opposing effects on fertility, the net effect of improvements in childhood nutrition on a woman’s fertility are uncertain. Using path analysis, we estimate the strength of the pathways between childhood growth and subsequent fertility outcomes in Guatemalan women studied prospectively since birth. Height for age z score at 24 months was positively related to body mass index (BMI kg/m2) and height (cm) in adolescence and to schooling attainment. BMI was negatively associated (−0.23 ± 0.09 years per kg/m2; p < . 05) and schooling was positively associated (0.38 ± 0.06 years per grade; p < .001) with age at first birth. Total associations with the number of children born were positive from BMI (0.07 ± 0.02 per kg/m2; p < .05) and negative from schooling (−0.18 ± 0.02 per grade; p < .01). Height was not related to age at first birth or the number of children born. Taken together, childhood nutrition, as reflected by height at 2 years, was positively associated with delayed age at first birth and fewer children born. If schooling is available for girls, increased growth during childhood will most likely result in a net decrease infertility.  相似文献   

10.
The availability of abortion provides insurance against unwanted pregnancies since abortion is the only birth control method which allows women to avoid an unwanted birth once they are pregnant. Restrictive state abortion policies, which increase the cost of obtaining an abortion, may increase women’s incentive to alter their pregnancy avoidance behavior, thereby reducing the likelihood of unwanted pregnancies. This study, using state-level data for the years 1982, 1992, and 2000, examines the impact of restrictive state abortion laws on teen pregnancy rates. The empirical results indicate that the price of an abortion, Medicaid funding restrictions, and informed consent laws reduce teen, minor teen and non-minor teen pregnancy rates. The empirical results suggest that these abortion policy restrictions affect the unprotected sexual activity of teens resulting in fewer unwanted teen pregnancies.  相似文献   

11.
Young J. Kim 《Demography》1986,23(3):451-465
The formula for the age distribution and other relationships that follow from it for any (non-stable) population presented by Preston and Coale are significant contributions to demography. The formulas summarize the relationships among various demographic measures precisely, and are formally analogous to the relationships that hold for stable populations. The significance of these formulas cannot be overstated; they allow us to understand clearly the relationships among demographic measures in any arbitrary population. However, when it comes to using them for estimating demographic measures when census data are defective, the method of estimation is still affected by defective data. The reason is that the series of age-specific growth rates reflects the observed census age distributions exactly so that any defects in the census data are summarized in the growth rates. This paper begins with the formulation of the discrete version of the "new synthesis" developed by Preston and Coale. With the discrete formulation, the three kinds of errors introduced when the continuous time formulas are applied to real data can be avoided. Then it is pointed out that when two accurate census data are available, the Preston-Coale procedure of "estimating" the age distribution at the second census is equivalent to checking the identity of the age distribution formula. Also "estimating" mortality by the procedure of Preston-Coale is shown to be equivalent to obtaining mortality directly from intercensal survival rates. That the procedure which involves the age-specific growth rates is equivalent to those that involve the intercensal survival rates may have escaped notice because there are no a priori constraints for patterns of age-specific growth rates to follow. The irregularity in growth rates due to defective data are not distinguishable from true irregularity that exists in the population, contrary to the well-known regularity in the pattern of survival rates in human populations.  相似文献   

12.
This paper analyzes the extent to which individual characteristics, the workplace situation, and regional policies influence the use and duration of parental leave in Spain. The research is based on a sample of 125,165 individuals, and 6,959 parental leaves covered in the “Muestra Continua de Vidas Laborales” (MCVL-2006). The MCVL consists of administrative register data, which include information from three different sources: The social security system, municipal and income tax Registers. We adopt a simultaneous equations approach to analyze the determinants of the use (logistic regression) and duration (event history analysis) of parental leave, which allows us to control for endogeneity and censored observations. Our results suggest that the Spanish parental leave scheme increases gender and social inequalities, insofar as it reinforces gender role specialization, and only encourages the reconciliation of work and family life among workers with a good position in the labor market (educated employees with a high and stable work status).  相似文献   

13.
A distribution of a social variable over a population assigns a level or value of the variable to each individual in the population. The present paper continues a study of methods of ordering distributions of a social variable that was begun in an earlier paper. The earlier paper addressed issues of meaningfulness of evaluative comparisons and then examined several fundamental criteria for social evaluation. The present paper focuses on a variety of methods of ordering distributions. It begins with additive extensions of a Pareto principle and then looks at a number of distributional dominance relations, all of which are based on individuals' preferences. Ordering methods that may be only marginally related to individuals' preferences are discussed in the latter part of the paper.  相似文献   

14.
Summary This paper discusses the analysis of selective predation experiments with two types of prey when the prey are not replaced after they have been removed by the predators. In an earlier paper (Manly et al., 1972) consideration was given to situations where the replication of experiments allows the estimation of standard errors from the experimental results; in the present paper a table of standard errors is given for a large range of experiments and replication is therefore no longer necessary. The standard errors were calculated on an electronic computer by solving the exact equations given in the earlier paper. The suggested method of analysis is illustrated using some data where the prey were red and yellow artificial ‘maggots’ and the predators were garden birds.  相似文献   

15.
16.

The Gompertz distribution, developed from the mortality “law”; long used by actuaries and demographers promises to be a useful distribution for many other demographic purposes as well. The continuous distribution can also be adapted to represent discrete data commonly encountered in demographic work, and maximum likelihood estimates of the two parameters are easily calculated using formulae developed in this paper, whether those data be continuous or discrete, truncated below or provided with observations in a final open‐ended interval.

The distribution is unimodel. The use of the truncated form of the distribution, however, allows the researcher to fit it to a wider range of observed distributions, including many for which the density function is monotonic decreasing.

Empirical studies using parity progression data of two high fertility populations indicate that the truncated Gompertz distribution in its discrete form provides a good overall picture of the parity distribution. Interestingly, the simple method of partial sums, commonly employed to fit the Gompertz function, appears to provide parameter estimates which are close to those estimated by maximum likelihood.  相似文献   

17.
Summary An approximate method for estimating the sample size in simple random sampling and a systematic way of transformation of sample data are derived by using the parameters α and β of the regression of mean crowding on mean density in the spatial distribution per quadrat of animal populations (Iwao, 1968). If the values of α and β have been known for the species concerned, the sample size needed to attain a desired precision can be estimated by simply knowing the approximate level of mean density of the population to be sampled. Also, an appropriate variance stabilizing transformation of sample data can be obtained by the method given here without restrictions on the distribution pattern of the frequency counts. Contribution from the Entomological Laboratory, Kyoto University No. 418. Contributions from JIBP-PT No. 52. Aided in part by a grant from the Ministry of Education for the special project research, ‘Studies on the dynamic status of biosphere’.  相似文献   

18.
Preston  Samuel H. 《Demography》1970,7(4):417-423

The method of decomposition is applied to rates of natural increase in order to elucidate the role played by age composition in the growth of populations. A population’s age distribution and fertility schedule are contrasted to those in a "stationary" population having the same mortality rates and having a fertility schedule equal to that of the observed population divided by its net reproduction rate. In this manner it is shown that about one-quarter to one-third of the growth of most current high-growth populations can be attributed to non-stationarity of their age distributions. This fraction will rise, as it has in most industrialized countries, if fertility is reduced and age distributions become middle-heavy. In projections of the 1963 Venezuelan female population with fertility rates declining by 20/0 and 1% annually, more than half of the growth (in numbers) that occurs prior to zero-growth attainment is contributed by non-stationarity of its intervening age distributions.

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19.
This study analyzes emigration propensities for natives and immigrants delineating among immigrant emigrants between return and onward migration. Results indicate that emigrants are positively selected in terms of upper education. Well-educated immigrants have a higher probability of leaving for third-country destinations than returning to countries of origin. Predicted age–income profiles for immigrants show that return migrants have higher adjusted mean income levels than non-emigrants up to the age of 40. Onward migrants have lower predicted income levels across the age distribution due to this group’s composition and relatively low employment levels in Sweden. Separate estimations by region of origin indicate that within each group, onward migrants are more positively selected then return migrants in terms of income.
Lena NekbyEmail: Fax: +46-44-8159482
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20.
Summary The study was carried out in two (A and B) citrus groves to clarify the spatial distribution patterns of eggs and larvae, and to analyse the mortality process of eggs. From the analysis by using the mean density and the mean crowding, it was clarified that the distributions of eggs were contagious and that larvae were more contagiously distributed than eggs. The τ andz indices showed that the operation of egg mortality was inversely density-dependent in both groves, and that the degree of inverse density-dependence was greater in A than in B grove. The spatial correlations between the emergence holes and the eggs or larvae in each tree, which were analysed by using ω index, showed that the distributions were more overlapping between the emergence holes and the larvae than the eggs. As the result of dividing trees into several groups according to the number of emergence holes, it was clarified that the survival rates of eggs were positively correlated with the number of emergence holes. In conclusion, inversely density-dependent mortality process was considered to be caused by lower mortality rates of eggs in the trees with more emergence holes. Especially in A grove, because the trees with more emergence holes were larger in diameter and more egg oviposition, the inversely density-dependent mortality process was considered to be detected more conspicuously than in B grove.  相似文献   

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