全文获取类型
收费全文 | 24082篇 |
免费 | 369篇 |
专业分类
管理学 | 3343篇 |
民族学 | 162篇 |
人才学 | 2篇 |
人口学 | 3522篇 |
丛书文集 | 84篇 |
教育普及 | 2篇 |
理论方法论 | 1781篇 |
综合类 | 635篇 |
社会学 | 11377篇 |
统计学 | 3543篇 |
出版年
2023年 | 70篇 |
2021年 | 79篇 |
2020年 | 207篇 |
2019年 | 260篇 |
2018年 | 1915篇 |
2017年 | 2041篇 |
2016年 | 1376篇 |
2015年 | 308篇 |
2014年 | 328篇 |
2013年 | 2274篇 |
2012年 | 763篇 |
2011年 | 1481篇 |
2010年 | 1280篇 |
2009年 | 1042篇 |
2008年 | 1111篇 |
2007年 | 1289篇 |
2006年 | 247篇 |
2005年 | 613篇 |
2004年 | 581篇 |
2003年 | 496篇 |
2002年 | 392篇 |
2001年 | 342篇 |
2000年 | 327篇 |
1999年 | 348篇 |
1998年 | 237篇 |
1997年 | 228篇 |
1996年 | 259篇 |
1995年 | 207篇 |
1994年 | 225篇 |
1993年 | 196篇 |
1992年 | 254篇 |
1991年 | 244篇 |
1990年 | 219篇 |
1989年 | 226篇 |
1988年 | 213篇 |
1987年 | 187篇 |
1986年 | 197篇 |
1985年 | 181篇 |
1984年 | 218篇 |
1983年 | 206篇 |
1982年 | 172篇 |
1981年 | 146篇 |
1980年 | 149篇 |
1979年 | 167篇 |
1978年 | 139篇 |
1977年 | 119篇 |
1976年 | 107篇 |
1975年 | 102篇 |
1974年 | 99篇 |
1973年 | 94篇 |
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
991.
Avery C. Edenfield Fredrik O. Andersson 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2018,29(5):1033-1043
This article examines how a social venture transitions from nascent to formal status and argues that the transformation of the organization set in motion by establishing formal boundaries is a deeply profound one. Drawing from the nonprofit and social entrepreneurship literature on what prompts and energizes individuals to initiate new not-for-profit ventures, and linking it to a notion of revolutionary crisis as organizations emerge and develop, we seek to illuminate and explore the tension, and its consequences, between nonprofit entrepreneurs and the organization they create as the new venture transitions from nascent to formal. We do this by presenting the results from an in-depth case study examining the gestation and boundary-forming phases of Robert’s Place Cooperative, a plucky start-up cooperative in a midsize Midwestern city. 相似文献
992.
Margherita Grazioli Carlotta Caciagli 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2018,29(4):697-711
This paper scrutinises the phenomenon of collective squatting for housing in Rome (Italy), which has reached remarkable proportions and developed new characteristics since the start of the 2008 crisis. Based upon two pieces of ethnographic research within the housing movement organisations Coordinamento Cittadino di Lotta per la Casa (Urban Coordination of Housing Struggles) and Blocchi Precari Metropolitani (Precarious Metropolitan Block), the authors aim to enlarge empirical knowledge of the case under study and provide renewed analytical instruments for understanding housing mobilisations. These organisations appear to be more than grassroots approaches to housing deprivation; they also represent alternative forms of social reproduction in post-welfare neoliberal cities. Indeed, squats configure themselves as sites for broader political elaboration. For this reason, we propose to analyse housing squatting using the notion of ‘urban commons’. The introduction of this notion to analyse housing movements helps in the theoretical elaboration of a re-appraised ‘right to the city’, in line with current urban challenges. 相似文献
993.
There are now three essentially separate literatures on the topics of multiple systems estimation, record linkage, and missing
data. But in practice the three are intimately intertwined. For example, record linkage involving multiple data sources for
human populations is often carried out with the expressed goal of developing a merged database for multiple system estimation
(MSE). Similarly, one way to view both the record linkage and MSE problems is as ones involving the estimation of missing
data. This presentation highlights the technical nature of these interrelationships and provides a preliminary effort at their
integration. 相似文献
994.
995.
996.
We deal with the double sampling plans by variables proposed by Bowker and Goode (Sampling Inspection by Variables, McGraw–Hill,
New York, 1952) when the standard deviation is unknown. Using the procedure for the calculation of the OC given by Krumbholz and Rohr (Allg.
Stat. Arch. 90:233–251, 2006), we present an optimization algorithm allowing to determine the ASN Minimax plan. This plan, among all double plans satisfying
the classical two-point-condition on the OC, has the minimal ASN maximum. 相似文献
997.
In some statistical problems a degree of explicit, prior information is available about the value taken by the parameter of interest, θ say, although the information is much less than would be needed to place a prior density on the parameter's distribution. Often the prior information takes the form of a simple bound, ‘θ > θ1 ’ or ‘θ < θ1 ’, where θ1 is determined by physical considerations or mathematical theory, such as positivity of a variance. A conventional approach to accommodating the requirement that θ > θ1 is to replace an estimator, , of θ by the maximum of and θ1. However, this technique is generally inadequate. For one thing, it does not respect the strictness of the inequality θ > θ1 , which can be critical in interpreting results. For another, it produces an estimator that does not respond in a natural way to perturbations of the data. In this paper we suggest an alternative approach, in which bootstrap aggregation, or bagging, is used to overcome these difficulties. Bagging gives estimators that, when subjected to the constraint θ > θ1 , strictly exceed θ1 except in extreme settings in which the empirical evidence strongly contradicts the constraint. Bagging also reduces estimator variability in the important case for which is close to θ1, and more generally produces estimators that respect the constraint in a smooth, realistic fashion. 相似文献
998.
Christopher R. Heathcote Borek D. Puza Steven P. Roberts 《Australian & New Zealand Journal of Statistics》2009,51(4):481-497
We consider two related aspects of the study of old‐age mortality. One is the estimation of a parameterized hazard function from grouped data, and the other is its possible deceleration at extreme old age owing to heterogeneity described by a mixture of distinct sub‐populations. The first is treated by half of a logistic transform, which is known to be free of discretization bias at older ages, and also preserves the increasing slope of the log hazard in the Gompertz case. It is assumed that data are available in the form published by official statistical agencies, that is, as aggregated frequencies in discrete time. Local polynomial modelling and weighted least squares are applied to cause‐of‐death mortality counts. The second, related, problem is to discover what conditions are necessary for population mortality to exhibit deceleration for a mixture of Gompertz sub‐populations. The general problem remains open but, in the case of three groups, we demonstrate that heterogeneity may be such that it is possible for a population to show decelerating mortality and then return to a Gompertz‐like increase at a later age. This implies that there are situations, depending on the extent of heterogeneity, in which there is at least one age interval in which the hazard function decreases before increasing again. 相似文献
999.
B. J. Gajewski R. Lee M. Bott U. Piamjariyakul R. L. Taunton 《Journal of applied statistics》2009,36(9):933-944
Data envelopment analysis (DEA) is a deterministic econometric model for calculating efficiency by using data from an observed set of decision-making units (DMUs). We propose a method for calculating the distribution of efficiency scores. Our framework relies on estimating data from an unobserved set of DMUs. The model provides posterior predictive data for the unobserved DMUs to augment the frontier in the DEA that provides a posterior predictive distribution for the efficiency scores. We explore the method on a multiple-input and multiple-output DEA model. The data for the example are from a comprehensive examination of how nursing homes complete a standardized mandatory assessment of residents. 相似文献
1000.
An approach to the analysis of time-dependent ordinal quality score data from robust design experiments is developed and applied to an experiment from commercial horticultural research, using concepts of product robustness and longevity that are familiar to analysts in engineering research. A two-stage analysis is used to develop models describing the effects of a number of experimental treatments on the rate of post-sales product quality decline. The first stage uses a polynomial function on a transformed scale to approximate the quality decline for an individual experimental unit using derived coefficients and the second stage uses a joint mean and dispersion model to investigate the effects of the experimental treatments on these derived coefficients. The approach, developed specifically for an application in horticulture, is exemplified with data from a trial testing ornamental plants that are subjected to a range of treatments during production and home-life. The results of the analysis show how a number of control and noise factors affect the rate of post-production quality decline. Although the model is used to analyse quality data from a trial on ornamental plants, the approach developed is expected to be more generally applicable to a wide range of other complex production systems. 相似文献