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891.
Scientists study seasonality in order to understand the effect of environmental, biological, and social factors on demographic events. Poor data quality can also affect seasonal variation in mortality and fertility statistics. The influence of error on seasonal data becomes crucial as researchers analyze timing and spacing of events in time-series analyses. In this study we examine the reported number of births by month in the Soviet Union for 1950, 1955, and 1958–85. The lowest number of births has typically occurred in December, and the highest in January. This seasonal pattern is not consistent with any plausible biological or behavioural explanation. It is probably an artifact of attributing births that actually occurred during the preceding December or earlier, to January. This implies that Soviet statistical practice has not followed the stated policy of attributing births to the period (day, month, year) in which they occur. A substantial reduction between the 1950s and 1985 in the December-January peak in reported births implies marked improvement in Soviet vital registration statistics. The Soviet case shows that characteristics of the registration system can impart a particular seasonal pattern to demographic data. It also shows that officially prescribed procedures are not always followed in data generation, even in centrally planned economies. Researchers should carefully examine the quality of seasonal data before concluding that the data reflect real variations in demographic behaviour. 相似文献
892.
Recent patterns of fertility in Europe show marked differences between countries. Recent United Kingdom and Irish fertility curves show ‘distortions’ in terms of a ‘bulge’ in early age fertility, distinct from the smoother curves of other European countries. These patterns may not be adequately described by mathematical functions used by previous studies to model fertility curves. A mixture model with two component distributions may be more appropriate. The suitability of the simple and mixture Hadwiger functions is examined in relation to the fertility curves of a number of European countries. While the simple Hadwiger model fits recent period age-specific fertility distributions for some countries, others which display a ‘bulge’ in early age fertility require a mixture Hadwiger model. Some of the parameters of the Hadwiger models appear to be related to familiar demographic indices. The simple and mixture Hadwiger models appear useful in describing and comparing fertility patterns across European countries. 相似文献
893.
This paper presents an analysis of levels of life expectancy and their patterns of change among six socio-economically differentiated sub-populations of England and Wales for the period 1851–1911. Differences in mortality levels among these sub-groups and their rates of change are analyzed with respect to three groups of explanatory variables, viz., environmental, stratification and demographic variables. Their relative importance for different periods is assessed and discussed. The findings show consistency with two previous studies, which have suggested that medical advances had little effect on the increase in life expectancy during the second half of the nineteenth century. The present paper supports the results of one study in that public health measures affected life expectancies earlier, while subsequently, the increase in standards of living was more important. 相似文献
894.
Jiajian Chen Robert D. Retherford Minja Kim Choe Li Xiru Cui Hongyan 《Population studies》2013,67(1):43-60
An analysis of data mainly from China's 1990 and 2000 censuses and 2005 mini-census shows how fertility decline between 1975 and 2005 in the province of Guangdong has been influenced by both fertility policy and economic and social development. Guangdong's development since 1975 has been very rapid and has attracted huge numbers of migrants from other provinces. The analysis of the province's fertility trend from 1975 shows clearly the influence of fertility policy on the trend. The analysis also shows that economic development has brought about large changes in population composition by urban/rural residence, education, occupation, and migration status, which, together with large fertility differentials by these characteristics, have contributed substantially to Guangdong's fertility decline, in large part through changes in proportions currently married. 相似文献
895.
896.
The participation of displaced populations in elections organizedas part of a peacebuilding process is increasingly recognizedas fundamental to the goal of peacebuilding itself. Guaranteesfor their electoral participation are important, first and foremost,as a matter of rights. They also are critical for the legitimacyof the election and its results, and thus for national and regionalstability. However, translating these provisions into practicecan be a complex task, which requires addressing a range oflegal, administrative, practical, and political issues. Thisarticle explores the relationship between peacebuilding andthe electoral participation of displaced populations, arguingthat it is not possible to build peace when exclusion is dejure or de facto built into the process. 相似文献
897.
Population and Environment - 相似文献
898.
899.
Weak ties, particularly those to potential employers, play a more important role than strong ties in the immigration of professionals to the United States. I operationalize network strength through the class of admission variable in the Immigration and Naturalization Service's public use data files,Immigrants Admitted to the United States, 1972–1992. I also examine the differential impact of legislative measures on the availability of strong versus weak ties for four groups of professionals: physicians, nurses, engineers and scientists. Not only do weak ties figure heavily on the immigration experiences of professionals, but those impacts affect women differently than men. Professional women rely more heavily on strong ties than on weak ties when compared with males in their respective professions, with the exception of nursing. These findings suggests a need for further study into the migration experiences of professionals as well as more research into how gendered networks develop among immigrant professionals and how those networks influence (either positively or negatively) immigrant adaptation to United States' society. 相似文献
900.
D. W. Snyder 《Population studies》2013,67(1):151-154
This not extends T. L. F. Devis's recent investigation of the relationship between tribal affiliation and fertility in Sierra Leone. Controls are introduced for age structure and economic variables. The findings suggest that tribal affiliation does not have much independent influence on fertility after these factors are allowed for. 相似文献