全文获取类型
收费全文 | 12692篇 |
免费 | 354篇 |
专业分类
管理学 | 1441篇 |
民族学 | 66篇 |
人口学 | 1145篇 |
丛书文集 | 63篇 |
教育普及 | 3篇 |
理论方法论 | 1087篇 |
综合类 | 131篇 |
社会学 | 6761篇 |
统计学 | 2349篇 |
出版年
2023年 | 81篇 |
2021年 | 94篇 |
2020年 | 216篇 |
2019年 | 284篇 |
2018年 | 390篇 |
2017年 | 480篇 |
2016年 | 353篇 |
2015年 | 246篇 |
2014年 | 345篇 |
2013年 | 2605篇 |
2012年 | 426篇 |
2011年 | 347篇 |
2010年 | 269篇 |
2009年 | 245篇 |
2008年 | 259篇 |
2007年 | 246篇 |
2006年 | 266篇 |
2005年 | 230篇 |
2004年 | 201篇 |
2003年 | 164篇 |
2002年 | 190篇 |
2001年 | 276篇 |
2000年 | 259篇 |
1999年 | 260篇 |
1998年 | 166篇 |
1997年 | 149篇 |
1996年 | 211篇 |
1995年 | 207篇 |
1994年 | 214篇 |
1993年 | 216篇 |
1992年 | 228篇 |
1991年 | 215篇 |
1990年 | 239篇 |
1989年 | 207篇 |
1988年 | 200篇 |
1987年 | 173篇 |
1986年 | 159篇 |
1985年 | 168篇 |
1984年 | 175篇 |
1983年 | 119篇 |
1982年 | 119篇 |
1981年 | 103篇 |
1980年 | 112篇 |
1979年 | 112篇 |
1978年 | 92篇 |
1977年 | 82篇 |
1976年 | 79篇 |
1975年 | 83篇 |
1974年 | 55篇 |
1973年 | 52篇 |
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
1.
Desirable system performance in the face of threats has been characterized by various management concepts. Through semistructured interviews with editors of journals in the fields of emergency response and systems management, a literature review, and professional judgment, we identified nine related and often interchangeably used system performance concepts: adaptability, agility, reliability, resilience, resistance, robustness, safety, security, and sustainability. A better understanding of these concepts will allow system planners to pursue management strategies best suited to their unique system dynamics and specific objectives of good performance. We analyze expert responses and review the linguistic definitions and mathematical framing of these concepts to understand their applications. We find a lack of consensus on their usage between interview subjects, but by using the mathematical framing to enrich the linguistic definitions, we formulate comparative visualizations and propose distinct definitions for the nine concepts. We present a conceptual framing to relate the concepts for management purposes. 相似文献
2.
D. C. Wickramarachchi B. L. Robertson M. Reale C. J. Price J. A. Brown 《Australian & New Zealand Journal of Statistics》2019,61(3):380-391
We present an algorithm for learning oblique decision trees, called HHCART(G). Our decision tree combines learning concepts from two classification trees, HHCART and Geometric Decision Tree (GDT). HHCART(G) is a simplified HHCART algorithm that uses linear structure in the training examples, captured by a modified GDT angle bisector, to define splitting directions. At each node, we reflect the training examples with respect to the modified angle bisector to align this linear structure with the coordinate axes. Searching axis parallel splits in this reflected feature space provides an efficient and effective way of finding oblique splits in the original feature space. Our method is much simpler than HHCART because it only considers one reflected feature space for node splitting. HHCART considers multiple reflected feature spaces for node splitting making it more computationally intensive to build. Experimental results show that HHCART(G) is an effective classifier, producing compact trees with similar or better results than several other decision trees, including GDT and HHCART trees. 相似文献
3.
Jiawen Chen Harvey J. Krahn Nancy L. Galambos Matthew D. Johnson 《Revue canadienne de sociologie》2019,56(1):30-48
Previous research on generativity, the desire to leave a legacy through establishing and guiding the next generation, has focused primarily on family life and civic engagement as pathways to midlife generativity. This paper proposes that intrinsically rewarding work can also be associated with a heightened sense of generativity in midlife. We test this hypothesis with data (n = 369 employed individuals, approximately 43 years old) from the 2010 wave of the Edmonton Transitions Study. Civic engagement was positively associated with midlife generativity, as predicted, but the hypothesized positive relationship between generativity and perceived parenting success was not found. Taking into account civic engagement and perceived parenting success, and controlling on a range of other variables, intrinsically rewarding work was positively associated with midlife feelings of generativity. 相似文献
4.
Cristian Oliva‐Aviles Mary C. Meyer Jean D. Opsomer 《Revue canadienne de statistique》2019,47(2):315-331
Estimates of population characteristics such as domain means are often expected to follow monotonicity assumptions. Recently, a method to adaptively pool neighbouring domains was proposed, which ensures that the resulting domain mean estimates follow monotone constraints. The method leads to asymptotically valid estimation and inference, and can lead to substantial improvements in efficiency, in comparison with unconstrained domain estimators. However, assuming incorrect shape constraints may lead to biased estimators. Here, we develop the Cone Information Criterion for Survey Data as a diagnostic method to measure monotonicity departures on population domain means. We show that the criterion leads to a consistent methodology that makes an asymptotically correct decision choosing between unconstrained and constrained domain mean estimators. The Canadian Journal of Statistics 47: 315–331; 2019 © 2019 Statistical Society of Canada 相似文献
5.
Jessica D. Freeman Jessica Elton Andrea Lambert South 《Journal of Family Communication》2019,19(3):261-276
ABSTRACTGrandfamilies, family structures in which grandparent(s) co-reside with and assume a primary caregiving role for at least one grandchild, are increasingly common in the United States. This qualitative, exploratory study, informed by family communication patterns theory (FCPT), illuminated the reported communication beliefs and practices of grandparents who serve as primary caregiver to at least one grandchild. Hybrid thematic analysis, combining FCTP with inductive analysis, was used to analyze 21 semi-structured interviews with grandparents. Results yielded four themes describing grandparents’ reported communicative practices: creating opportunities for listening and dialogue, talking about emotion, emphasizing openness, and allowing questioning; and three themes describing the impact of second-chance parenting: increased resources, acquired wisdom, and matured emotionally. Implications for grandfamily communication research in light of hybrid analyses and FCPT are discussed. 相似文献
6.
This paper aims to introduce the concept of symbolic correlation integral SC that is extensively used in many scientific fields. The new correlation integral SC avoids the noisy parameter 𝜀 of the classical correlation integral, defined by Grassberger and Procaccia (1983) and extensively used for constructing correlation-integral-based statistics, as in the BDS test. Once the free parameter 𝜀 disappears, it is possible to construct a nonparametric powerful test for independence that can also be used as a diagnostic tool for model selection. The symbolic correlation integral is also extended to deal with multivariate models, and a test for causality is proposed as an example of the theoretical power of the new concept. With extensive Monte Carlo simulations, the paper shows the good size and power performance of symbolic correlation-integral-based tests. 相似文献
7.
D. M. Zombade 《统计学通讯:理论与方法》2019,48(7):1621-1634
8.
Max Döring 《Journal of Statistical Computation and Simulation》2019,89(16):2997-3034
The aim of this article is to review existing goodness-of-fit tests for the exponential distribution under progressive Type-II censoring and to provide some new ideas and adjustments. In particular, we consider two-parameter exponentially distributed random variables and adapt the proposed test procedures to our scenario if necessary. Then, we compare their power by an extensive simulation study. Furthermore, we propose five new test procedures that provide reasonable alternatives to those already known. 相似文献
9.
García-Mata Osvaldo Zerón-Félix Mariana Briano Guadalupe 《Social indicators research》2022,163(1):111-135
Social Indicators Research - This paper aims to construct a financial well-being index and analyze its determinants among adults in Mexico. It employs multiple correspondence analysis, multiple... 相似文献
10.
M. Camino Ramón-Llorens Emma García-Meca M. Consuelo Pucheta-Martínez 《Long Range Planning》2019,52(6):101846
The objective of this paper is to analyze the effect of the professional, technical and relational background (human and social capital) of outside directors on promoting firm CSR disclosure. Following the Hillman et al. (2000) taxonomy of board members, we classify outside directors as business experts, support specialists and community influential, and examine whether business and technical expertise or political ties in the boardroom affect CSR disclosure.This study confirms that not all outside directors are equally effective in improving CSR disclosure and that only certain kinds of outside directors, those classified as support specialists, help promote it. On the other hand, our findings also show that directors with previous experience as politicians affect CSR disclosure negatively, probably due to their interests in safeguarding their reputation within the company, in avoiding public scrutiny and in protecting their political connections. In addition, our set of analysis with interaction effects reveals that powerful CEOs have the incentive to promote CSR-related strategies and to convince business experts and support specialist directors to enhance profitable sustainability strategies and transparency in CSR disclosure. Nevertheless, the powerful CEO effect is not enough to compensate the negative role of political directors on CSR reporting. Therefore, this paper supports the theories in favor of analyzing the multiple configurations of corporate governance mechanisms by adopting a holistic approach, and the need to combine these configurations in order to analyze their impact on CSR behavior. 相似文献