全文获取类型
收费全文 | 3073篇 |
免费 | 81篇 |
专业分类
管理学 | 481篇 |
民族学 | 24篇 |
人才学 | 1篇 |
人口学 | 269篇 |
丛书文集 | 27篇 |
理论方法论 | 308篇 |
综合类 | 34篇 |
社会学 | 1596篇 |
统计学 | 414篇 |
出版年
2023年 | 24篇 |
2022年 | 18篇 |
2021年 | 30篇 |
2020年 | 72篇 |
2019年 | 77篇 |
2018年 | 91篇 |
2017年 | 129篇 |
2016年 | 116篇 |
2015年 | 84篇 |
2014年 | 93篇 |
2013年 | 460篇 |
2012年 | 126篇 |
2011年 | 112篇 |
2010年 | 75篇 |
2009年 | 96篇 |
2008年 | 90篇 |
2007年 | 77篇 |
2006年 | 83篇 |
2005年 | 98篇 |
2004年 | 97篇 |
2003年 | 86篇 |
2002年 | 86篇 |
2001年 | 85篇 |
2000年 | 70篇 |
1999年 | 51篇 |
1998年 | 38篇 |
1997年 | 33篇 |
1996年 | 47篇 |
1995年 | 36篇 |
1994年 | 34篇 |
1993年 | 52篇 |
1992年 | 39篇 |
1991年 | 35篇 |
1990年 | 26篇 |
1989年 | 22篇 |
1988年 | 24篇 |
1987年 | 24篇 |
1986年 | 23篇 |
1985年 | 22篇 |
1984年 | 32篇 |
1983年 | 24篇 |
1982年 | 28篇 |
1981年 | 20篇 |
1980年 | 20篇 |
1979年 | 21篇 |
1978年 | 13篇 |
1977年 | 22篇 |
1975年 | 21篇 |
1974年 | 19篇 |
1973年 | 10篇 |
排序方式: 共有3154条查询结果,搜索用时 0 毫秒
51.
Thomas McCarthy 《Theory and Decision》1973,3(4):351-370
Philosophers of Science have recently put a good deal of energy into locating the precise methodological boundaries between the natural and the social sciences. The methodological affinities of the latter with certain aspects of the humanities have been as yet too little explored. A convenient starting point for this discussion, and one which is adopted in this paper, is a reconsideration of the role and nature of interpretive understanding in the social sciences. However, before a serious examination of this issue can be undertaken, a clearing operation on the encrusted misunderstandings which are part of the legacy of logical positivism is necessary. In this paper I argue that the neo-positivistic account of understanding rests on a misunderstanding of the concept; that a more adequate conception of the issues involved - and one closer to the traditional Verstehen problematic of Dilthey et al. - can be gleaned from the work of Peter Winch; and that this development is furthered in a number of important respects by recent work done in hermeneutic philosophy - especially that of H.-G. Gadamer. The discussion of Gadamer suggests that the problem of locating the boundaries with the humanities might be as serious a problem for the theory of the social sciences as has been that concerning the natural sciences. The paper concludes with several suggestions as to the implications of the analysis of understanding for the thesis of the methodological unity of the sciences. 相似文献
52.
Population and Environment - 相似文献
53.
Moving and union dissolution 总被引:1,自引:0,他引:1
This paper examines the effect of migration and residential mobility on union dissolution among married and cohabiting couples. Moving is a stressful life event, and a large, multidisciplinary literature has shown that family migration often benefits one partner (usually the man) more than the other Even so, no study to date has examined the possible impact of within-nation geographical mobility on union dissolution. We base our longitudinal analysis on retrospective event-history data from Austria. Our results show that couples who move frequently have a significantly higher risk of union dissolution, and we suggest a variety of mechanisms that may explain this. 相似文献
54.
Experience with branch and bound algorithms indicates that computational time is a function of not only the size of the problem, but also the nature of the input data. This paper formulates statistically-based variables which describe certain characteristics of the input data and experimentally evaluates their ability to predict computational time for one branch and bound algorithm, the relative location of facilities or “plant layout” problem. Results suggest that the described experimental procedure may be useful for an a priori assessment of the computational difficulty of specific branch and bound problems. 相似文献
55.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states. 相似文献
56.
Predictive factors of acculturation attitudes and social support among Asian immigrants in the USA 总被引:1,自引:0,他引:1
This study examines acculturation attitude and its relation to social support among Asian immigrants. The data were collected from 242 Korean, Indian and Filipino immigrants in the USA using the Acculturation Attitude Scale and the Social Support Index. Findings showed that Koreans had a less positive attitude toward acculturation than did Indian and Filipino participants. Acculturation attitude was positively correlated with educational level and English fluency. This study also found a negative correlation between acculturation attitude and social support. Social support from friends and English fluency were identified as significant predictor variables in determining the level of acculturation attitude. These findings not only contribute to social work education and practice, but also increase cultural sensitivity and awareness in working with these populations. 相似文献
57.
Thomas Fujiwara 《Econometrica : journal of the Econometric Society》2015,83(2):423-464
This paper studies the introduction of electronic voting technology in Brazilian elections. Estimates exploiting a regression discontinuity design indicate that electronic voting reduced residual (error‐ridden and uncounted) votes and promoted a large de facto enfranchisement of mainly less educated citizens. Estimates exploiting the unique pattern of the technology's phase‐in across states over time suggest that, as predicted by political economy models, it shifted government spending toward health care, which is particularly beneficial to the poor. Positive effects on both the utilization of health services (prenatal visits) and newborn health (low‐weight births) are also found for less educated mothers, but not for the more educated. 相似文献
58.
Kevin Glazebrook Colin Paterson Sandra Rauscher Thomas Archibald 《Production and Operations Management》2015,24(2):311-324
Lateral transshipments are a method of responding to shortages of stock in a network of inventory‐holding locations. Conventional reactive approaches only seek to meet immediate shortages. The study proposes hybrid transshipments which exploit economies of scale by moving additional stock between locations to prevent future shortages in addition to meeting immediate ones. The setting considered is motivated by retailers who operate networks of outlets supplying car parts via a system of periodic replenishment. It is novel in allowing non‐stationary stochastic demand and general patterns of dependence between multiple item types. The generality of our work makes it widely applicable. We develop an easy‐to‐compute quasi‐myopic heuristic for determining how hybrid transshipments should be made. We obtain simple characterizations of the heuristic and demonstrate its strong cost performance in both small and large networks in an extensive numerical study. 相似文献
59.
One important goal in multi-state modelling is to explore information about conditional transition-type-specific hazard rate functions by estimating influencing effects of explanatory variables. This may be performed using single transition-type-specific models if these covariate effects are assumed to be different across transition-types. To investigate whether this assumption holds or whether one of the effects is equal across several transition-types (cross-transition-type effect), a combined model has to be applied, for instance with the use of a stratified partial likelihood formulation. Here, prior knowledge about the underlying covariate effect mechanisms is often sparse, especially about ineffectivenesses of transition-type-specific or cross-transition-type effects. As a consequence, data-driven variable selection is an important task: a large number of estimable effects has to be taken into account if joint modelling of all transition-types is performed. A related but subsequent task is model choice: is an effect satisfactory estimated assuming linearity, or is the true underlying nature strongly deviating from linearity? This article introduces component-wise Functional Gradient Descent Boosting (short boosting) for multi-state models, an approach performing unsupervised variable selection and model choice simultaneously within a single estimation run. We demonstrate that features and advantages in the application of boosting introduced and illustrated in classical regression scenarios remain present in the transfer to multi-state models. As a consequence, boosting provides an effective means to answer questions about ineffectiveness and non-linearity of single transition-type-specific or cross-transition-type effects. 相似文献
60.
Missing covariate values is a common problem in survival analysis. In this paper we propose a novel method for the Cox regression model that is close to maximum likelihood but avoids the use of the EM-algorithm. It exploits that the observed hazard function is multiplicative in the baseline hazard function with the idea being to profile out this function before carrying out the estimation of the parameter of interest. In this step one uses a Breslow type estimator to estimate the cumulative baseline hazard function. We focus on the situation where the observed covariates are categorical which allows us to calculate estimators without having to assume anything about the distribution of the covariates. We show that the proposed estimator is consistent and asymptotically normal, and derive a consistent estimator of the variance–covariance matrix that does not involve any choice of a perturbation parameter. Moderate sample size performance of the estimators is investigated via simulation and by application to a real data example. 相似文献