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981.
This paper provides a novel approach to ordering signals based on the property that more informative signals lead to greater variability of conditional expectations. We define two nested information criteria (supermodular precision and integral precision) by combining this approach with two variability orders (dispersive and convex orders). We relate precision criteria with orderings based on the value of information to a decision maker. We then use precision to study the incentives of an auctioneer to supply private information. Using integral precision, we obtain two results: (i) a more precise signal yields a more efficient allocation; (ii) the auctioneer provides less than the efficient level of information. Supermodular precision allows us to extend the previous analysis to the case in which supplying information is costly and to obtain an additional finding; (iii) there is a complementarity between information and competition, so that both the socially efficient and the auctioneer's optimal choice of precision increase with the number of bidders.  相似文献   
982.
We study a continuous‐time principal–agent model in which a risk‐neutral agent with limited liability must exert unobservable effort to reduce the likelihood of large but relatively infrequent losses. Firm size can be decreased at no cost or increased subject to adjustment costs. In the optimal contract, investment takes place only if a long enough period of time elapses with no losses occurring. Then, if good performance continues, the agent is paid. As soon as a loss occurs, payments to the agent are suspended, and so is investment if further losses occur. Accumulated bad performance leads to downsizing. We derive explicit formulae for the dynamics of firm size and its asymptotic growth rate, and we provide conditions under which firm size eventually goes to zero or grows without bounds.  相似文献   
983.
We consider a single‐period assemble‐to‐order system that produces two types of end products to satisfy two independent and stochastic customer orders. Each type of product is used to fulfill a particular customer order and these two products share a common component. Furthermore, one customer may confirm her order before the other one, and the manufacturer needs to make a commitment immediately upon the receipt of each customer order on how many products to be delivered. We propose a model for optimizing the inventory and production decisions under the above ATO environment. We also extend our model to the situation where the manufacturer can fulfill the unsatisfied low‐priority demand using the left‐over inventories after fulfilling the high‐priority demand, in case the low‐priority customer arrives first. Numerical experiments are conducted, which provide some interesting insights on the impact of uncertain demand pattern.  相似文献   
984.
This paper proposes a comparison of the results of tax policy analysis obtained on the basis of unitary and collective representations of the household. We first generate labour supplies consistent with the collective rationality, by use of a model calibrated on microdata as described in Vermeulen et al. [Collective Models of Household Labor Supply with Nonconvex Budget Sets and Nonparticipation: A Calibration Approach (2006)]. A unitary model is then estimated on these collective data and unitary and collective responses to a tax reform are compared. We focus on the introduction of linear taxation in Germany. The exercise is replicated for other European countries and other topical reforms. Distortions due to the use of a unitary model turn out to be important in predicting labour supply adjustments, in the design of tax revenue neutral reforms, and in predicting a reform’s welfare implications.
Denis BeningerEmail:
  相似文献   
985.
This paper aims to develop an integrated policy index system using a Surface Measure of Overall Performance (SMOP) approach to comprehensively evaluate and compare the policy input and social output of the retirement payment system in urban and rural China, Hong Kong, Singapore and Taiwan. With this, a tool may be developed to help insightfully examine the old‐age income policies and appropriately, and perhaps theoretically in the future, categorize the types of retirement provisions or social security policies as a whole in the East and West. The results indicate that, particularly in urban China, Hong Kong, Singapore and Taiwan, a low level of de‐familization and medium and high levels of gender equality are the common features of these five pensions in China, Hong Kong, Singapore and Taiwan. Furthermore, it is found that the retirement provisions in China, Hong Kong, Singapore and Taiwan can well be divided into two groups based on the level of pension right protection and illustrate different characteristics between them accordingly. In addition, policy implications and suggestions for further reforms of these retirement payment schemes are elaborated in the light of the findings of this policy index system.  相似文献   
986.
Cet article analyse les expériences des femmes pendant la colonisation des Prairies au Canada en mettant l'accent sur leur travail, sur leurs aptitudes et sur les capacites d'adaptation a l'environnement naturel et aux obstacles économiques auxquels ces femmes et leurs families se sont mesurés. Bien que les attitudes patriarcales domi‐nantes, la législation et les principes économiques aient quelque peu occulté les contributions des femmes, les efforts qu'elles ont déployés en Saskatchewan illustrent la «souplesse» dont ont fait preuve les fermières dans l'accomplissement de tâches productives et non productives. L'article démontre que cette souplesse a constitué un facteur déterminant de la survie des fermes familiales et, par là, du succès de l'industrie du blé. This article analyzes women's experiences during the settlement of the western prairie region of Canada. Attention is placed on their labour, skills and ability to adapt to the natural environment and the economic obstacles that they and their families encountered. While prevailing patriarchal attitudes, legislation and economic principles obscured women's contributions, the efforts of women in Saskatchewan are used to highlight the “flexibility” exhibited by farm women in performing productive and non‐productive labour. It is argued that this flexibility was critical to the survival of family farms, and thus to the success of the wheat economy.  相似文献   
987.
Abstract. We consider a function defined as the pointwise minimization of a doubly index random process. We are interested in the weak convergence of the minimizer in the space of bounded functions. Such convergence results can be applied in the context of penalized M‐estimation, that is, when the random process to minimize is expressed as a goodness‐of‐fit term plus a penalty term multiplied by a penalty weight. This weight is called the regularization parameter and the minimizing function the regularization path. The regularization path can be seen as a collection of estimators indexed by the regularization parameter. We obtain a consistency result and a central limit theorem for the regularization path in a functional sense. Various examples are provided, including the ?1‐regularization path for general linear models, the ?1‐ or ?2‐regularization path of the least absolute deviation regression and the Akaike information criterion.  相似文献   
988.
The authors of this article have developed six probabilistic causal models for critical risks in tunnel works. The details of the models' development and evaluation were reported in two earlier publications of this journal. Accordingly, as a remaining step, this article is focused on the investigation into the use of these models in a real case study project. The use of the models is challenging given the need to provide information on risks that usually are both project and context dependent. The latter is of particular concern in underground construction projects. Tunnel risks are the consequences of interactions between site‐ and project‐ specific factors. Large variations and uncertainties in ground conditions as well as project singularities give rise to particular risk factors with very specific impacts. These circumstances mean that existing risk information, gathered from previous projects, is extremely difficult to use in other projects. This article considers these issues and addresses the extent to which prior risk‐related knowledge, in the form of causal models, as the models developed for the investigation, can be used to provide useful risk information for the case study project. The identification and characterization of the causes and conditions that lead to failures and their interactions as well as their associated probabilistic information is assumed to be risk‐related knowledge in this article. It is shown that, irrespective of existing constraints on using information and knowledge from past experiences, construction risk‐related knowledge can be transferred and used from project to project in the form of comprehensive models based on probabilistic‐causal relationships. The article also shows that the developed models provide guidance as to the use of specific remedial measures by means of the identification of critical risk factors, and therefore they support risk management decisions. Similarly, a number of limitations of the models are discussed.  相似文献   
989.
The purpose of this qualitative research was to explore the work experience of middle‐class, Korean full‐time mothers in their 50s. Interviews, observations, and photographs were collected from 11 Korean full‐time mothers to understand their work and career experiences. The data were analyzed by a case study qualitative method of inquiry. The themes that emerged from the data were paths to becoming full‐time mothers, multiple working roles from relationships, dialectical characteristics of work, meaning of full‐time mothering, and regrets and internalized biases for full‐time motherhood. The findings illustrate how full‐time mothers experience a sense of meaning and mattering from their work; how relationships and work are intertwined in their lives; and how gender, social class, and culture influence the work and relationships of full‐time mothers. Implications for counselors and researchers are discussed.  相似文献   
990.
Well-being equations are often estimated to generate monetary values for non-marketed activities. In such studies, utility is often approximated by either life satisfaction or General Health Questionnaire scores. We estimate and compare monetary valuations of informal care for the first time in the UK employing both measures, using longitudinal data on well-being and informal care provision. The choice of well-being measure has some effect on the estimated parameters and resulting monetary valuations, but any differences are not statistically significant. Further research is needed to confirm the comparability of these measures if researchers are to continue to use them interchangeably.  相似文献   
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