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1.
Sana M 《Demography》2010,47(3):801-820
Between 1994 and 2006, the ratio of foreign-born scientists and engineers (FSE) to native scientists and engineers (NSE) doubled. I decompose this change into a migration effect (which accounts for migration in general), a proportional college effect (which accounts for the relative proportions of college graduates among migrant and native workers), and a proportional science and engineering (S&E) effect (which accounts for the relative proportions of S&Es among migrant and native college-educated workers). Results show that the migration effect explains about three-quarters of the increase in FSE/NSE during the entire period under study. The proportional S&E effect, which captures changes in the ratio as a result of immigration of S&Es in excess of what would be expected from general migration alone, was largest in 1995–1998, which were years of sustained economic growth. Conversely, a slower economy coincided with a declining proportional S&E effect after 2000. Increases in the annual cap on H-1B visas, an important avenue of entry for foreign-born S&Es, had little effect on the ratio. In short, during 1994–2006, the association between economic swings and the specific, more than proportional migration of S&Es was much stronger than the association between the latter and changes in the H-1B cap.  相似文献   

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This paper analyzes the risk of poverty for self-identified lesbian, gay, and bisexual (LGB) people from mid-2013 through 2016 in the National Health Interview Survey, a nationally representative survey of households that includes a sexual orientation question based on identity (n = 112,143). The study tests the role of family structure—living with a spouse or partner and having children—on the risk of poverty for LGB and heterosexual respondents. After controlling for education, demographic, and health measures in a probit model, lesbians and gay men are as likely to be poor as similar heterosexuals, but bisexual women and men are significantly more likely to be poor, regardless of relationship status. Single and childless gay men are also more likely to be poor than single heterosexual men. Being in a relationship reduces the likelihood of poverty for people of all sexual orientations, but the data show evidence of a gender composition effect: married male same-sex couples are less likely and unmarried female same-sex couples more likely to be poor than their married counterparts. Marriage reduces gay men’s poverty risk more and children increase their poverty risk less than for heterosexual men.  相似文献   

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Yang Y 《Demography》2008,45(2):387-416
In this paper, I examine temporal changes in U.S. adult mortality by chronic disease cause of death and by sex over a 40-year period in the second half of the twentieth century. I apply age-period-cohort (APC) analyses that combine conventional approaches and a new method of model estimation to simultaneously account for age, period, and cohort variations in mortality rates for four leading causes of deaths, including heart disease, stroke, lung cancer, and breast cancer. The results show that large reductions in mortality since the late 1960s continued well into the late 1990s and that these reductions were predominately contributed by cohort effects. Cohort effects are found to differ by specific causes of death examined, but they generally show substantial survival improvements. Implications of these results are discussed with regard to demographic theories of mortality reductions, differential cohort accumulation of health capital and lifetime exposures to socioeconomic and behavioral risk factors, and period changes in diagnostic techniques and medical treatment.  相似文献   

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This paper employs commuter flow data from the 1990 and 2000 Decennial Censuses, and the 2006–2010 American Community Survey to replicate, evaluate, and extend the delineation of commuting zones first proposed by Tolbert and Killian (Labor Market Areas for the United States, 1987). Commuting zones offer a valuable tool for research on regional economies and have long served rural sociologists, economists, and geographers interested in a representation of the economy that acknowledges a connection between urban and rural areas and the capacity of economic systems to cross state lines. Our delineations provide both an update in the form of new delineations for 2010 and a revised set of 1990 and 2000 delineations that benefit from a consistent methodology across decades. We also provide a set of tools for comparing delineations across methods and over time. In presenting our revised delineations, we shed light on the role of expert opinion in the original delineations, the strengths and weaknesses of the original method, and offer suggestions for further revision of this tool that may better reflect the theoretical conception of commuting zones.  相似文献   

6.
William Hasty 《Mobilities》2014,9(3):350-368
Abstract

This paper follows some late-seventeenth and early eighteenth century pirate ships, focusing upon the moments when these most enigmatic and elusive of ocean-going vessels were appropriated and inhabited by mutinous mariners who literally risked their necks to take charge of them. This paper builds upon recent work in mobilities and oceanic studies which is developing more materialist perspectives as a means for better understanding the seas and ships as lived, dynamic spaces. By exploring some of the ways that pirate ships were crafted and modified, and then occupied, at the turn of the eighteenth century, this paper contributes new perspectives on the formation of piratical spaces and identities, and in the process, the role of mobilities and spatialities in creating spaces afloat. The paper argues for a greater acknowledgement of the role of process in the making of space and mobility at sea as a means of better understanding the complex geographies of the pirate ship and the experiences of those who sailed aboard them.  相似文献   

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White KJ 《Demography》2008,45(2):363-386
I investigate the relationship between county population change and farm dependence in the Great Plains region during the twentieth century, using spatial data analysis techniques. This research is rooted in a long-standing sociological and demographic interest in population responses to economic transitions and informs the theoretical understanding of urbanization processes. Using census and environmental data, the analysis challenges earlier assertions of a simple transition in the relationship between farm dependence and population change that accompanied modern technological advancements, namely tractors (the mechanization thesis). Rather than observing the proposed positive-to-negative shift, study results show a negative association throughout the pre- and post-mechanization periods. Partial support is found if the thesis is revised to consider the relationship between population change and the change in farm dependence rather than the level of farm dependence. Findings show mixed support for an alternative argument that nonfarm industries moderate the influence of farm dependence (the industry complex thesis). In contrast to earlier applications of the thesis, industrial relations in the Great Plains context are characterized by specialization rather than cooperation.  相似文献   

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In this article, we assess trends in residential segregation in the United States from 1960 to 2000 along several dimensions of race and ethnicity, class, and life cycle and present a method for attributing segregation to nested geographic levels. We measured segregation for metropolitan America using the Theil index, which is additively decomposed into contributions of regional, metropolitan, center city-suburban, place, and tract segregation. This procedure distinguishes whether groups live apart because members cluster in different neighborhoods, communities, metropolitan areas, or regions. Substantively, we found that the segregation of blacks decreased considerably after 1960 largely because neighborhoods became more integrated, but the foreign born became more segregated largely because they concentrated in particular metropolitan areas. Class segregation increased between 1970 and 1990 mainly because the affluent increasingly clustered in specific metropolitan areas and in specific municipalities within metropolitan areas. The unmarried increasingly congregated in center cities. The main purpose of this article is to describe and illustrate this multilevel approach to studying segregation.  相似文献   

10.
Lesbian, gay, bisexual, and transgender (LGBT) people in Cuba, Puerto Rico, and the United States are, to varying degrees, practitioners of the Afro-Cuban religion popularly known as Santería. Cuban and Puerto Rican forms of referencing LGBT populations are illustrated in this article, which is drawing from interviews and participant observation conducted in the United States, with close to 30 practitioners, many of whom were Cuban, Cuban American, and Puerto Rican. I discuss the ways in which Santería gatherings produce an alternative use of otherwise stigmatized language for "gay" practitioners. Through the use of distinctive language to reference all of these populations, we may rethink the relationship between identities and practices, and within that, gender presentations vis a vis identities.  相似文献   

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BackgroundObstetricians’ beliefs, attitudes, and clinical practices related to cesarean delivery on maternal request appears particularly important in the context of high cesarean section rate. However, few relative studies have been conducted.AimTo examine Chinese obstetricians’ attitudes, beliefs, and clinical practices with regard to cesarean delivery on maternal request, and to explore influencing factors associated with their practices of cesarean delivery on maternal request.MethodsA cross-sectional design was used. Self-administered anonymous questionnaires were distributed to eligible obstetricians at the Congress of the Shanxi Society of Gynecology and Obstetrics as well as the Congress of the Hainan Society of Gynecology and Obstetrics. The overall response rate was 526/649 (81.05%). Multivariate logistic regression models were used to examine independent effects on obstetrician’s clinical practices related to cesarean delivery on maternal request.FindingsObstetricians who agreed with pregnant women’s decision to choose cesarean section directly and believed the benefits of this procedure outweigh the risks had higher odds of performing cesarean delivery on maternal request. In addition, measures to decrease cesarean section at hospitals were associated with reduced likelihood to perform cesarean delivery on maternal request.ConclusionsThe present study showed a strong correlation between obstetricians’ attitudes, beliefs, as well as interventions to decrease cesarean section at hospitals and their clinical practices of cesarean delivery on maternal request. Measures to enhance the training of obstetricians and reduce CS at hospitals are essential to decrease the overall cesarean section rate in China.  相似文献   

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Donner WR 《Demography》2007,44(3):669-685
This study examines casualties from tornadoes in the United States between the years 1998 and 2000. A political model of human ecology (POET) was used to explore how the environment, technology, and social inequality influence rates of fatalities and injuries in two models. Data were drawn from four sources: John Hart's Severe Plot v2.0, National Weather Service (NWS) Warning Verification data, Storm Prediction Center (SPC) watch data, and tract-level census data. Negative binomial regression was used to analyze the causes of tornado fatalities and injuries. Independent variables (following POET) are classified in the following manner: population, organization, environment, and technology. Rural population, population density, and household size correspond to population; racial minorities and deprivation represent social organization; tornado area represents environment; and tornado watches and warnings, as well as mobile homes, correspond to technology. Findings suggest a strong relationship between the size of a tornado path and both fatalities and injuries, whereas other measures related to technology, population, and organization produce significant yet mixed results. Census tracts having larger populations of rural residents was, of the nonenvironmental factors, the most conclusive regarding its effects across the two models. The outcomes of analysis, although not entirely supportive of the model presented in this study, suggest to some degree that demographic and social factors play a role in vulnerability to tornadoes.  相似文献   

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Information,EducationandCommunicationChina'sinformation,educationandcommunication(IEC)programmeplaysanextremelyimportantrolei...  相似文献   

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Assumptions that single mothers are “time poor” compared with married mothers are ubiquitous. We tested theorized associations derived from the time poverty thesis and the gender perspective using the 2003–2012 American Time Use Surveys (ATUS). We found marital status differentiated housework, leisure, and sleep time, but did not influence the amount of time that mothers provided childcare. Net of the number of employment hours, married mothers did more housework and slept less than never-married and divorced mothers, counter to expectations of the time poverty thesis. Never-married and cohabiting mothers reported more total and more sedentary leisure time than married mothers. We assessed the influence of demographic differences among mothers to account for variation in their time use by marital status. Compositional differences explained more than two-thirds of the variance in sedentary leisure time between married and never-married mothers, but only one-third of the variance between married and cohabiting mothers. The larger unexplained gap in leisure quality between cohabiting and married mothers is consistent with the gender perspective.  相似文献   

18.
This comment builds on the work of Udry et al., developing a model of random variation of vital rates in small geographical areas. The model is based on the division of the variance of vital rates into three parts; that which would occur in a homogenous population; that due to population heterogeneity; and that due to yearly fluctuations in the underlying basis for the mean value of the probability of the vital event in question. Contrary to Udry et al., this model demonstrates that population heterogeneity must decrease the overall vital rate variance. Using birth rates presented in Udry et al., a test of the new model demonstrates the importance of the third factor, yearly fluctuations, in determining year-to-year variation in birth rates.  相似文献   

19.
This article uses Sedgwick's distinction between minoritizing and universalizing theories of sexuality to analyze variability in social psychologists' studies of anti-homosexual prejudice, focusing on studies of attitudes. Anti-homosexual prejudice was initially defined in conversation with gay liberationists and presumed, among other things, that fear of homoerotic potential was present in all persons. Later social psychologists theorized anti-homosexual prejudice in strict minoritizing terms: as prejudice towards a distinct out-group. In the first section of this paper we discuss corresponding shifts in the conceptualization of anti-homosexual attitudes. Next, using a universalizing framework, we re-interpret experiments on behavioral aspects of anti-homosexual attitudes which were originally conceptualized using a minoritizing framework, and suggest avenues for future research. Finally, we examine how queer theory might enrich this area of social psychological inquiry by challenging assumptions about the politics of doing scientific work and the utility of identity-based sexual politics.  相似文献   

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In this paper, I gauge the impact of veteran status on migration probabilities for black and white men in the late 20th century United States, comparing cohorts that were subject to various military staffing policies. I find that white veterans are more likely than are white non-veterans to live outside the state of their birth and to have recently migrated. These effects persist regardless of whether veterans were subject to the draft or the All Volunteer Force staffing policy, and are durable across the life course. Among blacks, elevated rates of veterans’ migration are first observed in 1980. These results illuminate a previously unidentified consequence of veteran status, and may point to a policy-linked mechanism through which prior military employment influences social mobility, the American labor force is redistributed, and the racial composition of states and localities is altered.  相似文献   

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