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781.
农产品生产主体质量安全多重认证行为研究   总被引:2,自引:0,他引:2       下载免费PDF全文
叠加认证能显著提升消费者对食品质量安全的信任程度和额外支付意愿。采用专业大户、合作社和龙头企业三类现代农业生产经营主体的数据,利用Heckman两阶段选择模型分析浙江省食用农产品生产主体的质量安全多重认证行为后发现,生产主体的多重认证行为除受生产主体的经营规模、人力资本、自有品牌状况等个体特征与市场结构特征显著影响外,还受到市场激励、主体责任压力和交易成本的显著影响。总体而言,生产主体的质量安全认证行为是在自身能力及环境约束下的成本收益权衡,生产主体的质量安全多重认证行为更主要是受市场激励和主体内在责任的驱动,而非政府的规制压力。  相似文献   
782.
本研究以伦理两难为切入点,探讨直销渠道中代理商的伦理决策过程以及道德强度对其伦理决策三阶段的影响。在文献综述和对直销代理商访谈的基础上,作者结合直销特点设计情境问卷对确定主题进行实证研究。研究结果表明:1.直销渠道中,代理商的伦理认知与伦理判断之间显著正相关、伦理认知与伦理意向之间显著负相关、伦理判断与伦理意向之间显著负相关。2.直销代理商的道德强度与伦理认知、伦理判断呈正相关关系,与伦理意向呈负相关关系。3.直销渠道中,道德强度中的结果大小、社会共识、效应可能性三个维度对代理商伦理决策三阶段均有显著影响,效应集中性维度仅在一个情境中对伦理判断具有显著影响。  相似文献   
783.
强苯赛浸种对水稻幼苗的根长、根重和根系体积都有促进作用,能提高根尖细胞分裂指数,能使胚根尖切段伸长和发根力增强,并能提高胚乳中淀粉酶活性和根系的呼吸强度。  相似文献   
784.
Parametric models for interval censored data can now easily be fitted with minimal programming in certain standard statistical software packages. Regression equations can be introduced, both for the location and for the dispersion parameters. Finite mixture models can also be fitted, with a point mass on right (or left) censored observations, to allow for individuals who cannot have the event (or already have it). This mixing probability can also be allowed to follow a regression equation.Here, models based on nine different distributions are compared for three examples of heavily censored data as well as a set of simulated data. We find that, for parametric models, interval censoring can often be ignored and that the density, at centres of intervals, can be used instead in the likelihood function, although the approximation is not always reliable. In the context of heavily interval censored data, the conclusions from parametric models are remarkably robust with changing distributional assumptions and generally more informative than the corresponding non-parametric models.  相似文献   
785.
This research presents the development of behavioral scoring models to predict future customer purchases in an online ordering application. Internet retailing lowers many barriers for customers switching between retailers for repeat purchases; thus, retaining existing customers is a key challenge for achieving profitability. Survey data were collected from 1,089 online customers of two companies. The subjective survey data were then used to predict purchases over the ensuing 12 months based on data from the company databases. The analysis illustrates the general applicability of predictive models of future customer purchases while also demonstrating the need to develop specific models tailored for an individual company's operating and marketing environment. The models provide insight on how companies can target marketing dollars more effectively and allocate investment across multiple operational areas for maximum return. The research answers a call for rigorous research in the area of predictive marketing, an area in which many companies are excelling but where there is a scarcity of detailed knowledge regarding application of such models.  相似文献   
786.
In a one‐principal two‐agent model with adverse selection and collusion among agents, we show that delegating to one agent the right to subcontract with the other agent always earns lower profit for the principal compared with centralized contracting. Delegation to an intermediary is also not in the principal's interest if the agents supply substitutes. It can be beneficial if the agents produce complements and the intermediary is well informed.  相似文献   
787.
To be cost‐effective, field service managers must balance the high cost of machine downtime with the high cost of cross‐training technicians in multiple skills. We study a field service system with three job types requiring three different skills. Each server has a primary skill, the cost of which is considered sunk, and up to two secondary skills, which is a managerial decision. We model two important characteristics that distinguish field services: server–job mismatch and the ratio of travel time to service time. We use a queueing framework and simulation to study three cross‐training decisions: the number of servers cross‐trained in secondary skills, the number of secondary skills each server should have, and the efficiency in each secondary skill. We find that complete cross‐training is cost‐effective in some field service situations. Typically, efficiency in secondary skills must be close to 100%, but when the probability of mismatch is high and the ratio of travel time to service time is high, efficiency in secondary skills must be less than 100%.  相似文献   
788.
In the literature of cooperative (co‐op) advertising, the focus of the research is on a relationship in which a manufacturer is the leader and retailers are followers. This relationship implies the dominance of the manufacturer over retailers. Recent market trends have shown a shift in power from manufacturers to retailers. Retailers, as a result, may now possess equal or even greater power than a manufacturer in some instances when it comes to retailing. Based on this new market phenomenon, we intend to explore the role of co‐op advertising in a manufacturer‐retailer supply chain through brand name investments, local advertising expenditures, and sharing rules of advertising expenses. Two co‐op advertising models are developed and compared. The first co‐op advertising model is based on the traditional leader‐follower relationship of a manufacturer and a retailer. The second model incorporates partnership into co‐op advertising coordination. Business examples and managerial implications of the models have been discussed. A cooperative bargaining technique is utilized to implement the partnership co‐op advertising model.  相似文献   
789.
Current opinion holds that Internet‐based supply chain integration with upstream suppliers and downstream customers (called “e‐integration” in this paper) is superior to traditional ways of doing business. This proposition remains untested, however, and similarly we know little about what are the upstream, internal, and downstream barriers to implementing e‐integration. This paper empirically addressed these questions using data from a large single nation study, and found (1) a positive link between e‐integration and performance, and (2) that internal barriers impeded e‐integration more than either upstream supplier barriers or downstream customer barriers. Findings from this study contribute to our theoretical understanding of implementing change in contemporary supply chains, and have important implications for manufacturers interested in improving their supply chain's performance using the Internet.  相似文献   
790.
This paper presents new identification conditions for the mixed proportional hazard model. In particular, the baseline hazard is assumed to be bounded away from 0 and ∞ near t = 0. These conditions ensure that the information matrix is nonsingular. The paper also presents an estimator for the mixed proportional hazard model that converges at rate N−1/2.  相似文献   
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