全文获取类型
收费全文 | 1254篇 |
免费 | 53篇 |
专业分类
管理学 | 34篇 |
民族学 | 13篇 |
人口学 | 528篇 |
丛书文集 | 30篇 |
理论方法论 | 35篇 |
综合类 | 340篇 |
社会学 | 38篇 |
统计学 | 289篇 |
出版年
2022年 | 11篇 |
2021年 | 6篇 |
2020年 | 20篇 |
2019年 | 14篇 |
2018年 | 16篇 |
2017年 | 17篇 |
2016年 | 24篇 |
2015年 | 16篇 |
2014年 | 40篇 |
2013年 | 129篇 |
2012年 | 93篇 |
2011年 | 103篇 |
2010年 | 95篇 |
2009年 | 53篇 |
2008年 | 58篇 |
2007年 | 77篇 |
2006年 | 82篇 |
2005年 | 61篇 |
2004年 | 76篇 |
2003年 | 66篇 |
2002年 | 49篇 |
2001年 | 53篇 |
2000年 | 42篇 |
1999年 | 31篇 |
1998年 | 22篇 |
1997年 | 10篇 |
1996年 | 9篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
排序方式: 共有1307条查询结果,搜索用时 0 毫秒
21.
22.
The 1979 National Longitudinal Survey of Youth is among the few surveys to provide multiple reports on respondents’ race and
ethnicity. Respondents were initially classified as Hispanic, black, or “other” on the basis of data collected during 1978
screener interviews. Respondents subsequently self-reported their “origin or descent” in 1979, and their race and Hispanic
origin in 2002; the latter questions conform to the federal standards adopted in 1997 and used in the 2000 census. We use
these data to (a) assess the size and nature of the multiracial population, (b) measure the degree of consistency among these
alternative race-related variables, and (c) devise a number of alternative race/ethnicity taxonomies and determine which does
the best job of explaining variation in log-wages. A key finding is that the explanatory power of race and ethnicity variables
improves considerably when we cross-classify respondents by race and Hispanic origin. Little information is lost when multiracial respondents are assigned to one of their reported race categories
because they make up only 1.3% of the sample.
相似文献
Alita NandiEmail: |
23.
联合国统计委员会会议是国际统计界的盛会,集中反映全球官方统计的最新成果和进展。本文对联合国统计委员会第50届会议最主要的若干问题,包括《2030年可持续发展议程》的数据和指标、官方统计基本原则、国家质量保证框架、官方统计使用大数据、国民账户体系、统计用途商业登记册、价格统计、住户调查、国际比较方案等领域的新发展进行了概述,从4个方面提出了国际官方统计的新发展对中国政府统计工作的启示。 相似文献
24.
25.
关于中国人口控制问题的商榷 总被引:1,自引:0,他引:1
中国人口占世界人口1/5,是世界人口最多的发展中国家。中国政府把计划生育政策定为基本国策,并取得了举世瞩目的成就。中国人口基数过大,人均耕地远小于国土面积与中国相当的美国,加上其他不利因素,经有关专家组研究,中国最大环境人口容量为16亿。又经预测,按现行中国人口政策,到2030年前后中国人口将达到16亿。中国人口控制喜忧参半,仍十分严峻,且任重而道远。因此,讨论了中国人口控制的成就和问题,并提出了若干建议供参考。 相似文献
26.
Robert Handfield 《决策科学》1993,24(3):581-602
Few studies of just-in-time (JIT) implementation examine their significance in make-to-order manufacturing environments. This study examines the relative importance of several operating variables that are characteristic features of JIT systems within such environments in North America. The results suggest that the most salient features of JIT for make-to-order and assemble-to-order firms are the elimination of waste (in the form of time and defects), reduced setup time, reduced lotsize, and a smaller pool of suppliers. In addition, the results suggest that the use of non-domestic suppliers can possibly hinder efforts at JIT implementation of materials procurement. 相似文献
27.
定居意愿是衡量流动人口转向稳定生活状态的重要指标,实则包含了居留意愿和落户意愿两方面的内容。基于2017年全国流动人口卫生计生动态监测数据,通过建立多项Logistic回归模型的方法,重点从与制度结构相关的“户籍地禀赋”与“流入地融合”两个维度,分析流动人口“居留-落户”的定居意愿状况及其影响因素。研究结果表明,户籍地禀赋性因素的“回流”效应和流入地融合性因素的“拉动”效应对流动人口不同层面定居意愿的影响存在差异:与责任、情感、伦理相关的户籍地禀赋性因素以及与经济融入、社会与文化接纳相关的流入地融合性因素对流动人口居留意愿的影响比较显著;与财富价值相关的户籍地禀赋性因素以及与城乡区位相关的流入地融合性因素对流动人口落户意愿的影响比较显著;制度融入因素、生活融入因素、身份认同因素则对两个维度的定居意愿都产生了显著影响。因此,对于具有定居意愿的流动人口,政府应该努力实现基本公共服务的全覆盖,激发流动人口参与社会建设、增强对流入地的身份认同与文化接纳等融合水平;对于没有定居意愿的流动人口,也需为其“回流”后在户籍地的再次融入提供良好的制度保障环境。 相似文献
28.
Isabel Baño-Piñero María Emilia Martínez-Roche Manuel Canteras-Jordana César Carrillo-García Esteban Orenes-Piñero 《Women and birth : journal of the Australian College of Midwives》2018,31(4):e239-e244
Background
The rates of breastfeeding worldwide are slowly improving since 1996. Europe is still trailing behind the global breastfeeding incidence and prevalence rates. Thus, breastfeeding promotion, protection, prolongation and support have become an important challenge as breastfeeding sharply decreases in the first six months of life.Objectives
The aim of this project is to determine, assess and identify the real impact of breastfeeding support networks in Murcia (Spain).Methods
After searching unsuccessfully for a validated questionnaire, a specific one was developed and validated for measuring the impact of formal and informal support networks through five dimensions: satisfaction, consultation, experience, problems and support. The questionnaire was provided to 500 mothers with experience in breastfeeding, who brought their children to baby paediatricians between 2 June and 27 November 2014. Upon completion of the survey and fieldwork, a detailed statistical analysis was conducted.Results
The degree of satisfaction perceived by the users of the services of support breastfeeding networks is remarkable. In addition, mothers who clarified their doubts and discussed their problems with health professionals and/or breastfeeding support networks were more likely to breastfeed for a longer duration compared to those who did not (p = 0.005). Furthermore, mothers who sought support in breastfeeding are more likely to breastfeed for more than 6 months (p < 0.0005).Conclusion
Based on this information, we conclude that breastfeeding support networks have a positive influence in the duration of a women’s decision to breastfeed. 相似文献29.
David J. Sharrow Jessica Godwin Yanjun He Samuel J. Clark Adrian E. Raftery 《Population studies》2018,72(1):1-15
In 2015, the United Nations (UN) issued probabilistic population projections for all countries up to 2100, by simulating future levels of total fertility and life expectancy and combining the results using a standard cohort component projection method. For the 40 countries with generalized HIV/AIDS epidemics, the mortality projections used the Spectrum/Estimation and Projection Package (EPP) model, a complex, multistate model designed for short-term projections of policy-relevant quantities for the epidemic. We propose a simpler approach that is more compatible with existing UN projection methods for other countries. Changes in life expectancy are projected probabilistically using a simple time series regression and then converted to age- and sex-specific mortality rates using model life tables designed for countries with HIV/AIDS epidemics. These are then input to the cohort component method, as for other countries. The method performed well in an out-of-sample cross-validation experiment. It gives similar short-run projections to Spectrum/EPP, while being simpler and avoiding multistate modelling. 相似文献
30.
中国老年人口健康预期寿命延长还是缩短?——基于Sullivan方法的实证研究 总被引:1,自引:0,他引:1
随着老年人口数量在总人口中不断增长,中国人口的总体健康水平。特别是老年人的健康预期寿命将会发生新的变化。中国老年人口的健康预期寿命是在增长还是在缩短?老年人口的健康预期寿命在总预期寿命中的比例是在增大还是在缩小?搞清楚这个问题对于我们合理地制定老龄政策至关重要。本文尝试应用国际上最为流行的Sullivan方法回答上述问题。 相似文献