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Parental influence on friendships between native (N = 5,683) and immigrant (N = 3,371) adolescents (aged ± 15) was investigated with the CILS4EU data of pupils in German and Dutch school classes (N = 446) and parents. The researchers examined whether parents affect friendships across group boundaries by shaping the structural opportunities to establish out‐group friends and their children's out‐group attitudes. The results show that if parents have more out‐group friends and if they consider it less important to maintain in‐group traditions, their children have more out‐group friends. Part of this relationship is mediated by children's out‐group attitudes. Some evidence is found that the opportunity structure mediates the relationship between parental characteristics and adolescent out‐group friendship. 相似文献
174.
Andrew Stone Euan Macpherson Ann Smith Christopher Jennison 《Pharmaceutical statistics》2015,14(6):455-463
Many oncology studies incorporate a blinded independent central review (BICR) to make an assessment of the integrity of the primary endpoint, progression free survival. Recently, it has been suggested that, in order to assess the potential for bias amongst investigators, a BICR amongst only a sample of patients could be performed; if evidence of bias is detected, according to a predefined threshold, the BICR is then assessed in all patients, otherwise, it is concluded that the sample was sufficient to rule out meaningful levels of bias. In this paper, we present an approach that adapts a method originally created for defining futility bounds in group sequential designs. The hazard ratio ratio, the ratio of the hazard ratio (HR) for the treatment effect estimated from the BICR to the corresponding HR for the investigator assessments, is used as the metric to define bias. The approach is simple to implement and ensures a high probability that a substantial true bias will be detected. In the absence of bias, there is a high probability of accepting the accuracy of local evaluations based on the sample, in which case an expensive BICR of all patients is avoided. The properties of the approach are demonstrated by retrospective application to a completed Phase III trial in colorectal cancer. The same approach could easily be adapted for other disease settings, and for test statistics other than the hazard ratio. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Preliminary Development and Validation of the Social and Emotional Health Survey for Secondary School Students 总被引:1,自引:0,他引:1
Michael J. Furlong Sukkyung You Tyler L. Renshaw Douglas C. Smith Meagan D. O’Malley 《Social indicators research》2014,117(3):1011-1032
This study reports on the preliminary development and validation of the Social and Emotional Health Survey (SEHS) with a sample of 4,189 (51 % female) California students in Grades 8, 10, and 12. The SEHS was designed to measure the psychological building blocks of adolescents’ positive mental health and is operationalized in the present study by a theoretical model comprised of 12 measured indicators that form four first-order domains (belief-in-self, belief-in-others, emotional competence, and engaged living) that, in turn, contribute to one underlying, second-order meta-construct called covitality. This study was the first to investigate the validity and utility of the adolescent covitality construct, which is conceptualized as the synergistic effect of positive mental health resulting from the interplay among multiple positive-psychological building blocks. Findings from confirmatory factor analyses, invariance analysis, and latent means testing all supported the theoretical model underlying the SEHS, indicating that the second-order covitality model was the best fit for both males and females. Results from a path-modeling analysis indicated that covitality was a strong predictor of students’ subjective well-being (operationalized as a composite of life satisfaction, positive affect, and negative affect), and findings from additional concurrent validity analyses indicated that adolescents’ covitality level was significantly associated with self-reported academic achievement, perceptions of school safety, substance use, and experiences of depressive symptoms. Implications for theory, practice, and future research are discussed. 相似文献
177.
Projections of total population have been evaluated extensively, but few studies have investigated the performance of projections by age. Of those that did, most focused on projections for countries or other large areas. In this article, we evaluate projections by age for Florida and its counties, as produced and published between 1996 and 2010 by the Bureau of Economic and Business Research at the University of Florida. We first compare the precision and bias of projections of total population with the precision and bias of projections by age, at both the state and county levels. This is followed by a more detailed examination of county-level projection errors for individual age groups, first in the aggregate and then disaggregated by sex and population size. The second part of the analysis focuses on a number of adjustments that were implemented in projections published in 2006 and 2009. Intended to improve accuracy, these adjustments involved updates to the base population, fertility rates, and survival rates. We compare the accuracy of projections incorporating these adjustments with the accuracy of projections excluding them. We believe this study offers a unique opportunity to examine a variety of characteristics regarding the forecast accuracy of small-area population projections by age. 相似文献
178.
Objective. This research examines the migration behavior of the elderly, recognizing that the older and younger elderly may make different decisions and have different consequences for the states in which they live. Methods. Using U.S. Census migration flow data, we describe the movements of the younger and older elderly. Our econometric analysis brings together the wisdom of elderly migration research that focuses on motives (amenity vs. return/assistance) and the Tiebout‐related research that considers the effects of policy. Results. We find that all elderly age groups avoid moving to states with high estate/inheritance/gift taxes, although the effect weakens with age. Likewise, the younger elderly appear to be “shopping around” for destinations with a temperate climate and favorable government policies regarding income taxes and welfare spending, whereas the older elderly are more likely to be “driven out” of their origin state by a high cost of living and income and property taxes. Conclusions. Our findings suggest that both the patterns of migration and the factors that affect migration decisions differ between the younger and older elderly. 相似文献
179.
Tom W. Smith 《Social science research》2002,31(4)
Different methods of measuring inter-racial contacts produce large differences in the level of the same. Experiments conducted on the 1998 General Social Survey indicate that estimates of how many people have inter-racial friends are much higher when a direct question is asked, intermediate when a three-step procedure is used, and the least when a name-generator, network approach is used. Cognitive and social desirability reasons for these effects are discussed. 相似文献
180.
The growing relative number, the improved economic well-being, and the migration of elderly retirees is not only reshaping the social and economic structure of many areas, it is also modifying both long-term and short-run patterns of economic growth. Transfer payments and property incomes, two of the most important source of elderly income, have been among the leading sources of national income growth over the past several decades. Unlike most labor-related industry sources of earnings, the level of transfer payments and property incomes received by the residents of the region is not directly dependent upon local economic activity. Consequently, as transfer payments and property incomes of elderly retirees become increasingly important sources of income and purchasing power within a region, they also can alter regional short-run cyclical patterns of income growth. This article examines the pattern of growth of transfer payments and property incomes in the context of national economic cycles, and explores the implication of those findings on metropolitan and nonmetropolitan Nevada economies. 相似文献