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851.
We describe a regression-based approach to the modelling of age-, order-, and duration-specific period fertility, using retrospective survey data. The approach produces results that are free of selection biases and can be used to study differential fertility. It is applied to Demographic and Health Survey data for Ethiopia, Kenya, Tanzania, and Zimbabwe to investigate differential trends in fertility by education. Parity progression fell and the intervals following each birth lengthened between the 1970s and 2000s in all four countries. Fertility fell most among women with secondary education. In contrast to other world regions, postponement of successive births for extended periods accounted for much of the initial drop in fertility in these African countries. However, family size limitation by women with secondary education in Ethiopia and Kenya and longer birth spacing in Zimbabwe also played significant roles. Thus, birth control is being adopted in Eastern Africa in response to diverse changes in fertility preferences. 相似文献
852.
Many important questions and theories in demography focus on changes over time, and on how those changes differ over geographic
and social space. Space-time analysis has always been important in studying fertility transitions, for example. However, demographers
have seldom used formal statistical methods to describe and analyze time series of maps. One formal method, used widely in
epidemiology, criminology, and public health, is Knox’s space-time interaction test. In this article, we discuss the potential
of the Knox test in demographic research and note some possible pitfalls. We demonstrate how to use familiar proportional
hazards models to adapt the Knox test for demographic applications. These adaptations allow for nonrepeatable events and for
the incorporation of structural variables that change in space and time. We apply the modified test to data on the onset of
fertility decline in Brazil over 1960–2000 and show how the modified method can produce maps indicating where and when diffusion
effects seem strongest, net of covariate effects. 相似文献
853.
Alisson F. Barbieri Edson Domingues Bernardo L. Queiroz Ricardo M. Ruiz José I. Rigotti José A. M. Carvalho Marco F. Resende 《Population and environment》2010,31(5):344-370
This research contributes to an understanding of the relationship between climate change, economic impacts and migration.
We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven
by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular
relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels
of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately,
the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary
economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact
severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country.
Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian
public policy and planning. 相似文献
854.
Aaron M. McCright 《Population and environment》2010,32(1):66-87
This study tests theoretical arguments about gender differences in scientific knowledge and environmental concern using 8 years
of Gallup data on climate change knowledge and concern in the US general public. Contrary to expectations from scientific
literacy research, women convey greater assessed scientific knowledge of climate change than do men. Consistent with much
existing sociology of science research, women underestimate their climate change knowledge more than do men. Also, women express
slightly greater concern about climate change than do men, and this gender divide is not accounted for by differences in key
values and beliefs or in the social roles that men and women differentially perform in society. Modest yet enduring gender
differences on climate change knowledge and concern within the US general public suggest several avenues for future research,
which are explored in the conclusion. 相似文献
855.
Nicole Tieben Paul M. de Graaf Nan Dirk de Graaf 《Research in social stratification and mobility》2010
Recent developments in educational transitions research suggest a decomposition of qualitative dimensions within educational levels that are (nearly) universal. However, research on long-term trends of social stratification in the structurally tracked educational system of the Netherlands has not been published previously. In the Netherlands, the secondary educational level is divided into four hierarchical tracks which each lead to different options for subsequent educational decisions. A rapid increase of participation in the higher tracks over time however, may have changed the background-specific distribution of early track placement. This paper improves upon previous research on educational inequality by incorporating a long-term perspective into tracking research. The secondary level of the Dutch educational system is decomposed into its four tracks, using a time frame that covers cohorts that entered secondary education between 1946 and 1998. The application of multinomial logit regressions reveals that the choice of a secondary track is strongly depending on social background features, measured as education of the parents and occupational status of the father. We found linear downward trends of effects for fathers’ occupation in the intermediate tracks for the cohorts that entered secondary education between WWII and the 90s. The effects of parental education also decrease after WWII, but the trend is curvilinear and not enduring. Unexpectedly, the effects almost reach their previous level in the youngest cohort. Our results furthermore suggest that a controversial reform of the educational system in 1968 neither triggered nor accelerated equalization of secondary education, although it resulted in a growth of participation in senior general education (HAVO). 相似文献
856.
Janevic MR Janz NK Kaciroti N Dodge JA Keteyian SJ Mosca L Clark NM 《Journal of women & aging》2010,22(4):255-272
Using behavioral self-regulation processes may facilitate exercise among older women with heart disease. Data from women in a heart disease-management program (n = 658, mean 73 years), was used to explore associations among exercise self-regulation components (i.e., choosing to improve exercise and observing, judging, and reacting to one's behavior) and exercise capacity. General linear models showed that choosing exercise predicted higher exercise self-regulation scores postprogram and 8 months later. In turn, these scores predicted greater improvements in exercise capacity concurrently and 8 months later. Interaction analyses revealed that the effect of self-regulation on exercise capacity was stronger among women who chose to work on exercise. 相似文献
857.
Anne M. Gadermann Kimberly A. Schonert-Reichl Bruno D. Zumbo 《Social indicators research》2010,96(2):229-247
This study introduces the Satisfaction with Life Scale adapted for Children (SWLS-C) and presents psychometric findings regarding
its validation. The SWLS-C was adapted from the Satisfaction with Life Scale (SWLS; Diener et al. 1985), which is one of the most commonly used measures to assess satisfaction with life in adults. Three subject matter experts
adapted the SWLS by changing the wording of the item stem and response format in order to make it more understandable for
children. A stratified random sample of 1,233 students (48% girls) in grades 4–7 (mean age 11 years and 7 months) provided
data on the SWLS-C and measures of optimism, self-concept, self-efficacy, depression, emphatic concern, and perspective taking.
The SWLS-C demonstrated a unidimensional factor structure and high internal consistency. Furthermore, differential item functioning
and differential scale functioning analyses indicated that the SWLS-C measures satisfaction with life in the same way for
different groups of children (i.e., with regard to gender, first language learned at home—English vs. other language(s) than
English—and across different grades) at the item and at the scale level. Associations between scores on the SWLS-C and demographic
variables were statistically non-significant or of small effect size. In addition, the SWLS-C showed evidence of convergent
and discriminant validity in relation to the other measures. Our results indicate that the SWLS-C is a psychometrically sound
instrument that demonstrated evidence of construct validity for this age group. Limitations and future directions are discussed. 相似文献
858.
859.
Melina M. Bersamin Byron L. Zamboanga Seth J. Schwartz M. Brent Donnellan Monika Hudson Robert S. Weisskirch 《Journal of sex research》2014,51(1):43-51
A multiethnic sample of single, heterosexual, emerging-adult college students (N = 3,907) ages 18 to 25, from 30 institutions across the United States, participated in a study about identity, culture, psychological well-being, and risky behaviors. Given ongoing debates about the connection between casual sex and psychological adjustment, in the current study we assessed the cross-sectional association of participation in casual sex with psychological well-being and distress. A greater proportion of men (18.6%) compared to women (7.4%) reported having had casual sex in the month prior to assessment. Structural equation modeling indicated that casual sex was negatively associated with well-being (ß = .20, p < .001) and positively associated with psychological distress (ß = .16, p < .001). Gender did not moderate these associations. For emerging-adult college students, engaging in casual sex may elevate risk for negative psychological outcomes. 相似文献
860.
Melissa A. Lewis Dana M. Litt Jessica M. Cronce Jessica A. Blayney Amanda K. Gilmore 《Journal of sex research》2014,51(1):86-96
Individuals who engage in risky sexual behavior face the possibility of experiencing negative consequences. One tenet of social learning theory is that individuals engage in behaviors partly based on observations or perceptions of others’ engagement in those behaviors. The present study aimed to document these norms–behavior relationships for both risky and protective sexual behaviors, including alcohol-related sexual behavior. Gender was also examined as a possible moderator of the norms–behavior relationship. Undergraduate students (n = 759; 58.0% female) completed a Web-based survey, including various measures of drinking and sexual behavior. Results indicated that students underestimate sexual health-protective behaviors (e.g., condom use and birth control use) and overestimate the risky behaviors (e.g., frequency of drinking prior to sex, typical number of drinks prior to sex, and frequency of casual sex) of their same-sex peers. All norms were positively associated with behavior, with the exception of condom use. Furthermore, no gender differences were found when examining the relationship between normative perceptions and behavior. The present study adds to the existing literature on normative misperceptions as it indicates that college students overestimate risky sexual behavior while underestimating sexual health-protective behaviors. Implications for interventions using the social norm approach and future directions are discussed. 相似文献