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891.
Lee RD 《Journal of the American Statistical Association》1974,69(347):607-617
Time series analysis of fertility can improve demographic forecasts. The optimal forecast and its variance for births to an age-structured population subject to serially correlated random fertility are developed. The general case in which the fertility process had arbitrary autoregressive structure is dealt with and then the 4 special cases of white noise, 1st-order autoregressive, 2nd-order autoregressive, and random walk are considered. Consequently, it is determined that the predictions and their variances are highly sensitive to the autoregressive structure of fertility and, therefore, if stochastic models are to be used for prediction, they must emphasize this aspect of the problem. Preliminary empirical efforts to model the time series of U.S. fertility from 1917 to 1972 proved unsuccessful, but it is obvious that at least a 2nd-order autoregressive scheme is require d. The analysis proveded should be helpful in: 1) any application of the procedures requires a successful parameterization of the fertility process; 2) fertility variations could be decomposed into the effects of nuptiality and marital fertility and then births and marriages could be jointly predicted; and 3) the simplifying approximations should be dropped and each age-specific rate could be analyzed and predicted. 相似文献
892.
Wolfers D 《Population studies》1971,25(3):535-536
Abstract Contraceptive use in the early post-partum months is, for the majority of women, without any direct protective value because, whilst not ovulating, they are not exposed to the risk of pregnancy. This does not, of course, imply that contraception should be delayed until signs of the resumption of ovulation appear, as for many women the first sign of such resumption is pregnancy. There are, besides, logistic and psychological reasons which make early post-partum contraception advisable. It does, however, demand that any calculation of the demographic effects of contraceptive use should make due allowance for this null period of use. 相似文献
893.
894.
895.
896.
With an identical data base—the SRCICPS election studiesconducted over the 1952–1976 period—scholars arriveat conflicting conclusions about the future politics of theSouth. One problem is alternative regional definitions—thesurvey category Solid South (which includes the states of theformer Confederacy minus Tennessee) or the combined categoriesSolid South and Border South. Another problem is the choiceto analyze native whites, whites, or all election participants.Based on data presented here, these choices are not neutral;rather, they influence the research findings. If the intentis to build upon the aggregate data-based research of Key andothers, one should use the Solid South definition. Moreover,if the intent is to predict about the future politics of theSouth, one should analyze all election participants. 相似文献
897.
Roberts DF 《Population studies》1971,25(3):465-479
Abstract The eruption of the volcano on Tristan da Cunha in 1961 and the subsequent arrival of the island population in the United Kingdom provided a unique opportunity for studying the health of this formerly isolated community. During their stay, while the facilities and services of modern medicine were made available to them, investigations of many facets of their general biology were made under the auspices of the Medical Research Council, co-ordinated by Dr. H. E. Lewis. Analysis of their demographic history was essential to understand many features of their disease pattern, and the results of this analysis are presented here. They are of interest in that they not only show some consistent trends in the common variables of demography, but also demonstrate biological principles, some perhaps for the first time in man, which may be fundamental in the process of colonization as a biological phenomenon, e.g. the initial difficulty of establishment of a population in a new area, the curious demographic structure that may emerge in its earliest years, the bottleneck effect of population-size reduction, the founder principle. 相似文献
898.
How do family arrangements affect subjective well-being? We investigate this issue using data pooled from the IsssA and HILDA, both large, representative national samples of Australia (pooled n=38 447). Our regression analysis of cross-sectional and panel data examines how large are the differences in life satisfaction according to marital status and cohabitation. We find that women and men in formal marriages experience higher levels of life satisfaction than do people in other family arrangements. Moreover, both multiple tests in the cross-section, and tests controlling for prior happiness in the panel analysis, suggest that this is a causal relationship. Aggregating up the levels of life satisfaction generated by different marriage and cohabitation arrangements across a lifetime, suggests that a life-long marriage is the most satisfying. Early divorce followed by an enduring second marriage is little worse (because little time is spent outside the married state). But divorce without remarriage, or long lasting cohabitation without formal marriage, reduce the lifetime sum of subjective well-being by 4–12% for both women and men. 相似文献
899.
Gove WR 《Journal of health and social behavior》2004,45(4):357-375
This paper provides a new way of conceptualizing the career of the mentally ill. Most persons who experience an episode of a serious mental disturbance lead a normal life, while a few persons lead lifetimes that revolve around their mental disorders. The processes leading to either result can only be understood by integrating the traditional labeling and psychiatric perspectives with lay understandings of the concepts of "mental illness" and "nervous breakdowns." A selection of key concepts from these perspectives leads to a better understanding of the different paths persons take as they move through the pre-patient, inpatient, and post-patient phases of the "career of the mentally ill." This perspective makes understandable a number of counterintuitive relationships. For example, it explains why most hospitalized mental patients (1) have a negative stereotype of the "mentally ill," (2) do not perceive themselves as "mentally ill, yet (3) perceive themselves as benefiting from treatment, and (4) do not progress into a career of secondary deviance. 相似文献
900.
McLeod JD Pescosolido BA Takeuchi DT White TF 《Journal of health and social behavior》2004,45(1):53-67
Psychiatric medication use for children has increased dramatically over the past three decades. Despite substantial media attention to the issue, little is known about how the lay public feels about the use of psychiatric medications for children. Drawing on theories of medicalization, we describe and analyze Americans' attitudes towards the use of psychiatric medications generally and Prozac specifically for children described as having three types of behavioral problems. Using data from the 1998 General Social Survey's Pressing Issues in Health and Medical Care Module, we find that more Americans (57%) are willing to use psychiatric medications for children who have expressed suicidal statements than for "oppositional" behaviors (34.2%) or for hyperactivity (29.5%). Across the board, respondents are less willing to give Prozac than the general class of psychiatric medications. While socio-demographics do little to identify Americans with differing positions, the strongest and most consistent correlates of willingness to give psychiatric medications to children are trust in personal physicians, general attitudes towards psychiatric medications, and the respondent's expressed willingness to take psychiatric medications herself or himself. 相似文献