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1.
An attempt has been made in this paper to measure social development. There has been some limited use of per capita national income as a measure of development. A number of social indicators from various societal areas may, alternatively, better represent social development of a region. A composite index of selected social indicators has been proposed as a measure of social development. Certain existing methods of construction of composite indexes have been examined and new methods proposed using the variance-covariance matrix and intercorrelation matrix of the indicators and the concept of (Euclidean) distance. Two examples of intertemporal and international comparisons have been presented to illustrate the proposed methods.The author is grateful to Prof. M. Mukherjee under whose supervision and guidance this work was carried out. However, the views expressed in this paper are those of the author and not of the institution to which he belongs.  相似文献   

2.
Studies on population history are often based on incomplete records of life histories. For instance, in studies using data obtained from family reconstitution, the date of death is right censored (by migration) and the censoring time is never observed. Several methods for the correction of mortality estimates are proposed in the literature, most of which first estimate the number of individuals at risk and then use standard techniques to estimate mortality. Other methods are based on statistical models. In this paper all methods are reviewed, and their merits are compared by applying them to simulated and to seventeenth-century data from the English parish of Reigate. An ad hoc method proposed by Ruggles performs reasonably well. Methods based on statistical models, provided they are sufficiently realistic, give comparable accuracy and allow the estimation of several other quantities of interest, such as the distribution of migration times.  相似文献   

3.
Significant research attention has been given to historical patterns of marital fertility transitions in currently industrialized countries. Specifically, studies consider the time of the onset of fertility decline and its distribution among populations or population subgroups; the distribution of pre-decline parital fertility levels; and/or the rate of marital fertility decline. Analyses of pre-decline fertility level and its rate of decline, however, depend upon the procedure used to estimate the time of fertility decline. The Princeton European Fertility Project is the most prominent historical fertility study ever conducted. The procedure employed to estimate the timing parameter in these Princeton studies is described. An alternative statistical procedure is then proposed for detecting the onset of the transition from high to low marital fertility; the method may also be used to find the termination point of decline where the sequence of fertility variables is long enough. Both methods produce maximum likelihood least squares estimates, but the form proposed in the text has conceptual advantages.  相似文献   

4.
Various methods have been proposed to estimate demographic parameters such as mortality from field census data. Simple methods proposed earlier are applicable only for limited situations. For example, the Kiritani-Nakasuji-Manly method is applicable only if individuals are observable until their death. Improved methods proposed later are not subject to such limitations, but are not so widely used in the field of applied entomology, probably because of the complexity of the calculations involved. In this paper, I propose an intermediate method that requires only a pocket calculator, considering the practical convenience for field scientists. This method, which is a modification of the Kiritani-Nakasuji-Manly method, gives an estimate of the number of individuals entering a stage from the frequency of two stages when the stage duration is known.  相似文献   

5.
Summary An age-structured population model is used as a vehicle for presenting a method for the analysis of interactions between pairs of insect pest control methods. This analysis is based on partitioning the total mortality acting on a population into its constituent components from all known sources. Pairwise critical mortality curves are then constructed which represent the combined mortality required for eradicating the pest population. Effort curves are then constructed from computing the mortality resulting from a given amount of control effort. The convolution of the critical mortality curves and the effort curves then yields the isoclines formed by the effort required of two control methods in combination to achieve eradication. This analysis allows the prediction of either synergism or interference between the control methods and also helps explain patterns observed in previous modelling of such combinations of pest control methods.  相似文献   

6.
This paper proposes a new index of governance based on the Alkire-Foster methodology and compares it with the Mo Ibrahim Index of African Governance. The proposed new index improves on existing measures of governance in two ways. First, it is able to incorporate both cardinal and ordinal variables without having to assign cardinal meaning to ordinal variables. The cardinalization of ordinal variables can lead to ambiguous rankings depending on the choice of the cardinal scale. Second, by borrowing the mechanism of cutoffs found in poverty measurement literature, the index can focus attention on nations deprived in terms of governance. The index is computed for the 48 countries of the Mo Ibrahim Foundation’s data. The groups of best-performing and worst-performing nations identified by each of the two methods are largely similar. However, there are some differences among the middle order governance nations. An additional advantage of the proposed methodology is that it involves counting each country’s achievements in the dimensions of governance, which can be presented in a report card of governance.  相似文献   

7.
Summary An index of intensity of sexual selection proposed by Nishida (1992: Res. Popul. Ecol. 34: 373–382) was examined. Two examples were presented to show that Nishida's index was not free from confounding effect of mortality schedule. Importance of removing the phylogenetic effects in comparative analyses was also discussed.  相似文献   

8.
The two methods commonly used to assess the effect of sex preferences on fertility are inadequate to the task. Parity progression ratio analyses suffer from logical problems stemming from the heterogeneity of sex preferences and the riskiness of fertility decisions. While conjoint measurement-dominance procedures overcome these logical problems, they cannot yield quantitative estimates of the impact of sex preferences on fertility. A stopping rule measure which overcomes these limitations is proposed and described and its potential for determining the effect of sex predetermination methods on population is discussed.  相似文献   

9.
城镇贫困人口基本生活需求测定模型比较与应用   总被引:1,自引:0,他引:1  
张靖 《西北人口》2010,31(4):7-11
本文在现有文献的基础上,提出了测算城镇贫困人口基本生活需求的四种基本方法,并通过实证研究,发现应采用收入比例法的测算结果或四种方法测算结果的均值作为城镇贫困人口基本生活需求的标准。研究结果表明。运用收入比例法,我国城镇贫困人口基本生活需求将从2010年的9465.20元增长到2020年的29212.41元,年均递增11.93%:四种计算方法的均值将从2010年的7438.41元增长到2020年的19189.98元,年均递增9.94%。  相似文献   

10.
Using data from the 1970 National Fertility Study, the trend in the initiation of contraception prior to the first pregnancy is examined. This trend is of interest because of its relationship to the tempo of familybuilding. Using data from a recent marriage cohort, it is shown that use before the first pregnancy is related to age at marriage, age at termination of first pregnancy and the probability of having a premarital conception. For women first married during the decade of the 1960’s, there was a substantial increase in the proportion using contraception before the first pregnancy. This trend is found among both white Catholics and white non-Catholics, but not among blacks. An examination of the specific method used by women using contraception before the first pregnancy reveals a shift from reliance on the traditional methods of diaphragm, condom and douche by the earlier birth cohorts to the use of the pill by the more recent cohorts. An appendix examines the reliability of various measures of the interval of first use of contraception.  相似文献   

11.
A population density grid of the European Union   总被引:5,自引:0,他引:5  
This paper describes four methods used to produce dasymetric population density grids combining population data per commune with CORINE Land Cover, a map available for all countries of the European Union. An accuracy assessment has been carried out for five countries for which a very reliable 1-km population density grid exists; the improvement, compared with the choropleth map per commune, ranges between 20% for the weakest result in Finland and 62% for the best result in the Netherlands. The best results are obtained with a method using logit regression to integrate information from the point survey LUCAS (Land Use/Cover Area frame Survey); however, performance differences between methods are moderate. The dasymetric grid is distributed free of charge by the European Environment Agency, for non-commercial use.  相似文献   

12.
This reply criticizes Kim's note as incorrectly characterizing the essential feature of the method proposed for life table construction. The method suggested for estimating N(a), the number attaining age 2 during the intercensal period, is to make a separate estimate of the contribution to N (a) made by each single-year cohort that attains 'a' during the period between censuses. Each cohort estimate is constructed by interpolation, utilizing as data the recorded number in the relevant single-year cohorts in the 2 censuses. 2 methods of interpolation were proposed. 1 is an iterative procedure that constructs a preliminary life table by linear interpolation for each cohort and then derives more refined interpolation factors from this preliminary life table. The other procedure derives interpolation factors on the assumption that the proportionate distribution of deaths by age as each cohort moves from the earlier to the later census date is the same as the proportionate distribution of deaths by age over the same age range in a model life table. The advantage of the proposed procedure is that it supplies better estimates of N (a) than do alternative methods. The author concedes that a life table calculated from accurately recorded deaths and an accurately enumerated population would ordinarily be superior. However, he also notes that in the absence of registered deaths data, there is no precise enough conventional method to yield accurate values of average intercensal single-year age-specific mortality rates from nothing more than 2 accurate censuses 11 years apart. A common procedure for calculating life expectation at a very advanced age is to calculate the reciprocal of the death rate among persons over the age in question.  相似文献   

13.
Chinese population statistics are collated from the time of the Western Han Dynasty (A.D. 2) to 19 5 3, including statistics of population and households for provinces as well as for China as a whole. Evidence bearing on the definitions of the statistics, methods of compilation, and reliability of the figures as measures of population size and change, is summarized. An "emended series " of population totals for China proper, A.D. 2 to 1953 is presented, excluding figures which are clearly defective.  相似文献   

14.
Abstract Mortality from abortion is low in the Netherlands to-day, and approximately equal to mortality at delivery. Calculations suggest that about 4,000 abortions occur in Amsterdam every year, of which about 2,100 are induced. The abortion rate shows a very gradual decline after the Second World War. An investigation of the social background of women with induced abortion showed no relationship between occupational group and the incidence of abortion, but a strong negative correlation between religion and abortion. Abortion was more common among women with disturbed relationships in their own or parental families. Induced abortion usually occurred in pregnancies resulting from failure of contraception; these failures were caused not by lack of knowledge of good contraceptives, but by ineffective practice of contraception. The inability to use contraceptive methods in an effective way is related to a lack of communication between the two partners, and to a negative attitude of the women towards sex. An attempt has been made to formulate a theory of the causes of induced abortion among the women interviewed in Amsterdam.  相似文献   

15.
The magnitude increase of Urban Quality of Life studies is directly connected with the increase of the urban population in the world. Urban Quality of Life is a hierarchical multi-attribute concept whose attributes can be defined and evaluated by several kinds of methods such as Monetary (Hedonic Price, Willingness-to-pay, Cost-Benefit, Positional Value), Subjective (life satisfaction, subjective wellbeing, ranking/rating evaluation) and Quantitative (how many urban attractions there are in the city, and how they are distributed on its planimetry). As real examples of monetary approaches, 107 empirical literature results are briefly shown, quantifying the increase of property value in relation to urban factors such as green, open space, noise, public transport, pleasant view, etc. The result of a Willingness-to-Pay survey, and the definition of Positional Value are also shown; it is the part of property value coming from the characteristics of the area in which the property is. An analysis of Turin illustrated that the quality of the area (the Positional Value) can change the value of a property up to 143 %. This value is, in a certain way, a monetary mirror of the quality of life of the areas. As a concrete example of subjective approaches two rating method surveys on Turin are rapidly exposed, as well as a recent subjective wellbeing study comparing the life satisfaction in cities and in the countryside. As quantitative approaches are proposed the concepts of Isobenefit Lines and the Isobenefit Orography, both from the spatial urban amenities distribution and quantity.  相似文献   

16.
Summary An understanding of most plant virus disease epidemics requires a consideration of the population dynamics of insect vectors that transmit the viruses and the relationship between vector and disease dynamics. Some simple analytical (continuous-time) models are proposed for nonpersistently transmitted viruses that center on the absolute  相似文献   

17.
"An age-structured model of population dynamics with age-dominance is proposed and analyzed. Existence and uniqueness of solutions are established as well as the uniqueness and local asymptotic stability of steady-states. Conditions for convergence to or oscillation about the steady-state are specified in some cases." (SUMMARY IN FRE)  相似文献   

18.
Forecasting Mortality: A Parameterized Time Series Approach   总被引:2,自引:0,他引:2  
This article links parameterized model mortality schedules with time series methods to develop forecasts of U.S. mortality to the year 2000. The use of model mortality schedules permits a relatively concise representation of the history of mortality by age and sex from 1900 to 1985, and the use of modern time series methods to extend this history forward to the end of this century allows for a flexible modeling of trend and the accommodation of changes in long-run mortality patterns. This pilot study demonstrates that the proposed procedure produces medium-range forecasts of mortality that meet the standard tests of accuracy in forecast evaluation and that are sensible when evaluated against the comparable forecasts produced by the Social Security Administration.  相似文献   

19.
Research on the schooling implications of fertility transitions often faces an aggregation problem: despite policy interest in macro-level outcomes, empirical studies usually focus on the micro-level effects of sibsize on schooling. This article proposes an aggregation framework for moving from micro- to macro-level associations between fertility and schooling. The proposed framework is an improvement over previous aggregation methods in that it considers concurrent changes in the effects of sibsize, socioeconomic context, and family structure. The framework is illustrated with data from six sub-Saharan countries. Possible extensions are discussed.  相似文献   

20.
Herson  Jay 《Demography》1975,12(3):467-470
A method is proposed for standardizing life table cumulative failure rates for various cohorts so that they are adjusted to the distribution of exposure by age group for a particular cohort. An approximate standard error for the standardized cumulative failure rate is presented. Application of the methodology is illustrated by a numerical example.  相似文献   

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