首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10490篇
  免费   3篇
管理学   1532篇
民族学   99篇
人口学   2415篇
理论方法论   497篇
综合类   286篇
社会学   4468篇
统计学   1196篇
  2022年   1篇
  2020年   3篇
  2019年   1篇
  2018年   1657篇
  2017年   1654篇
  2016年   1073篇
  2015年   35篇
  2014年   39篇
  2013年   45篇
  2012年   327篇
  2011年   1149篇
  2010年   1047篇
  2009年   781篇
  2008年   826篇
  2007年   1000篇
  2006年   1篇
  2005年   229篇
  2004年   252篇
  2003年   213篇
  2002年   88篇
  2001年   7篇
  2000年   13篇
  1999年   6篇
  1998年   1篇
  1996年   30篇
  1995年   1篇
  1994年   1篇
  1990年   1篇
  1988年   8篇
  1984年   1篇
  1981年   2篇
  1978年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
This study illuminates the association between cigarette smoking and adult mortality in the contemporary United States. Recent studies have estimated smoking-attributable mortality using indirect approaches or with sample data that are not nationally representative and that lack key confounders. We use the 1990–2011 National Health Interview Survey Linked Mortality Files to estimate relative risks of all-cause and cause-specific mortality for current and former smokers compared with never smokers. We examine causes of death established as attributable to smoking as well as additional causes that appear to be linked to smoking but have not yet been declared by the U.S. Surgeon General to be caused by smoking. Mortality risk is substantially elevated among smokers for established causes and moderately elevated for additional causes. We also decompose the mortality disadvantage among smokers by cause of death and estimate the number of smoking-attributable deaths for the U.S. adult population ages 35+, net of sociodemographic and behavioral confounders. The elevated risks translate to 481,887 excess deaths per year among current and former smokers compared with never smokers, 14 % to 15 % of which are due to the additional causes. The additional causes of death contribute to the health burden of smoking and should be considered in future studies of smoking-attributable mortality. This study demonstrates that smoking-attributable mortality must remain a top population health priority in the United States and makes several contributions to further underscore the human costs of this tragedy that has ravaged American society for more than a century.  相似文献   
992.
This study introduces a new sample that links people and families across 1860, 1880, and 1900 census data to explore the intergenerational impact of slavery on black families in the United States. Slaveholding—the number of slaves owned by a single farmer or planter—is used as a proxy for experiences during slavery. Slave family structures varied systematically with slaveholding sizes. Enslaved children on smaller holdings were more likely to be members of single-parent or divided families. On larger holdings, however, children tended to reside in nuclear families. In 1880, a child whose mother had been on a farm with five slaves was 49 % more likely to live in a single-parent household than a child whose mother had been on a farm with 15 slaves. By 1900, slaveholding no longer had an impact. However, children whose parents lived in single-parent households were themselves more likely to live in single-parent households and to have been born outside marriage.  相似文献   
993.
This article presents an assessment of individual uncertainty about longevity. A survey performed on 3,331 French people enables us to record several survival probabilities per individual. On this basis, we compute subjective life expectancies (SLE) and subjective uncertainty regarding longevity (SUL), the standard deviation of each individual’s subjective distribution of her or his own longevity. It is large and equal to more than 10 years for men and women. Its magnitude is comparable to the variability of longevity observed in life tables for individuals under 60, but it is smaller for those older than 60, which suggests use of private information by older respondents. Our econometric analysis confirms that individuals use private information—mainly their parents’ survival and longevity—to adjust their level of uncertainty. Finally, we find that SUL has a sizable impact, in addition to SLE, on risky behaviors: more uncertainty on longevity significantly decreases the probability of unhealthy lifestyles. Given that individual uncertainty about longevity affects prevention behavior, retirement decisions, and demand for long-term care insurance, these results have important implications for public policy concerning health care and retirement.  相似文献   
994.
Rebecca Glauber 《Demography》2018,55(5):1663-1680
Many studies have shown that women pay a wage penalty for motherhood, whereas men earn a wage premium for fatherhood. A few recent studies have used quantile regression to explore differences in the penalties across the wage distribution. The current study builds on this research and explores trends in the parenthood penalties and premiums from 1980 to 2014 for those at the bottom, middle, and top of the wage distribution. Analyses of data from the Current Population Survey show that the motherhood wage penalty decreased, whereas the fatherhood wage premium increased. Unconditional quantile regression models reveal that low-, middle-, and high-earning women paid similar motherhood wage penalties in the 1980s. The motherhood wage penalty began to decrease in the 1990s, but more so for high-earning women than for low-earning women. By the early 2010s, the motherhood wage penalty for high-earning women was eliminated, whereas low-earning women continued to pay a penalty. The fatherhood wage premium began to increase in the late 1990s, although again, more so for high-earning men than for low-earning men. By the early 2010s, high-earning men received a much larger fatherhood wage premium than low- or middle-earning men.  相似文献   
995.
In Africa and elsewhere, educated women tend to marry later than their less-educated peers. Beyond being an attribute of individual women, education is also an aggregate phenomenon: the social meaning of a woman’s educational attainment depends on the educational attainments of her age-mates. Using data from 30 countries and 246 birth cohorts across sub-Saharan Africa, we investigate the impact of educational context (the percentage of women in a country cohort who ever attended school) on the relationship between a woman’s educational attainment and her marital timing. In contexts where access to education is prevalent, the marital timing of uneducated and highly educated women is more similar than in contexts where attending school is limited to a privileged minority. This across-country convergence is driven by uneducated women marrying later in high-education contexts, especially through lower rates of very early marriages. However, within countries over time, the marital ages of women from different educational groups tend to diverge as educational access expands. This within-country divergence is most often driven by later marriage among highly educated women, although divergence in some countries is driven by earlier marriage among women who never attended school.  相似文献   
996.
997.
Local area population forecasts have a wide variety of uses in the public and private sectors. But not enough is known about the errors of such forecasts, particularly over the longer term (20 years or more). Understanding past errors is valuable for both forecast producers and users. This paper (i) evaluates the forecast accuracy of past local area population forecasts published by Australian State and Territory Governments over the last 30 years and (ii) illustrates the ways in which past error distributions can be employed to quantify the uncertainty of current forecasts. Population forecasts from the past 30 years were sourced from State and Territory Governments. Estimated resident populations to which the projections were compared were created for the geographical regions of the past projections. The key features of past forecast error patterns are described. Forecast errors mostly confirm earlier findings with regard to the relationship between error and length of projection horizon and population size. The paper then introduces the concept of a forecast ‘shelf life’, which indicates how far into the future a forecast is likely to remain reliable. It also illustrates how past error distributions can be used to create empirical prediction intervals for current forecasts. These two complementary measures provide a simple way of communicating the likely magnitude of error that can be expected with current local area population forecasts.  相似文献   
998.
This paper presents a stochastic model to forecast the German population and labor supply until 2060. Within a cohort-component approach, our population forecast applies principal components analysis to birth, mortality, emigration, and immigration rates, which allows for the reduction of dimensionality and accounts for correlation of the rates. Labor force participation rates are estimated by means of an econometric time series approach. All time series are forecast by stochastic simulation using the bootstrap method. As our model also distinguishes between German and foreign nationals, different developments in fertility, migration, and labor participation could be predicted. The results show that even rising birth rates and high levels of immigration cannot break the basic demographic trend in the long run. An important finding from an endogenous modeling of emigration rates is that high net migration in the long run will be difficult to achieve. Our stochastic perspective suggests therefore a high probability of substantially decreasing the labor supply in Germany.  相似文献   
999.
This paper investigates long-term earnings differentials between African American and white men using data that match respondents in the Survey of Income and Program Participation to 30 years of their longitudinal earnings as recorded by the Social Security Administration. Given changing labor market conditions over three decades, we focus on how racial differentials vary by educational level because the latter has important and persistent effects on labor market outcomes over the course of an entire work career. The results show that the long-term earnings of African American men are more disadvantaged at lower levels of educational attainment. Controlling for demographic characteristics, work disability, and various indicators of educational achievement does not explain the lower long-term earnings of less-educated black men in comparison to less-educated white men. The interaction arises because black men without a high school degree have a larger number of years of zero earnings during their work careers. Other results show that this racial interaction by educational level is not apparent in cross-sectional data which do not provide information on the accumulation of zero earnings over the course of 30 years. We interpret these findings as indicating that compared to either less-educated white men or highly educated black men, the long-term earnings of less-educated African American men are likely to be more negatively affected by the consequences of residential and economic segregation, unemployment, being out of the labor force, activities in the informal economy, incarceration, and poorer health.  相似文献   
1000.
Over the twentieth and twenty-first centuries, veterans have been more likely to enter into race/ethnic intermarriages than non-veterans. Theories of race/ethnic intermarriage variously point to how minority race/ethnicity, race/ethnically diverse social settings, progressive racial attitudes, and high socioeconomic status increase individuals’ likelihood of intermarrying. Veterans’ unique racial and socioeconomic characteristics may contribute to their greater likelihood of intermarrying relative to non-veterans: larger percentages of veterans than non-veterans are members of racial and ethnic minority groups, while military service increases individual service members’ long-term economic and educational prospects. At the same time, veterans share in common their exposure to the unique military environment, which may increase their likelihood of intermarriage by diversifying their social circles, and subjecting their attitudes and behavior to group norms that are more explicitly egalitarian than those of society at large. The present study considers these two possible explanations for veterans’ greater likelihood of intermarriage. We use data on seven cohorts of men over six decades in the Current Population Survey, representing a total of 1,456,742 observations, to decompose the difference in likelihood of racial intermarriage between veterans and non-veterans among married men aged 18–65. We find that across cohorts and decades, veterans’ greater likelihood of intermarrying is not fully explained by their race/ethnic and socioeconomic composition. We argue that veterans’ greater likelihood of intermarrying may therefore be driven by their exposure to the military environment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号