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881.
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883.
In 1971, President Nixon declared war on cancer. Thirty years later, many declared this war a failure: the age‐adjusted mortality rate from cancer in 2000 was essentially the same as in the early 1970s. Meanwhile the age‐adjusted mortality rate from cardiovascular disease fell dramatically. Since the causes that underlie cancer and cardiovascular disease are likely dependent, the decline in mortality rates from cardiovascular disease may partially explain the lack of progress in cancer mortality. Because competing risks models (used to model mortality from multiple causes) are fundamentally unidentified, it is difficult to estimate cancer trends. We derive bounds for aspects of the underlying distributions without assuming that the underlying risks are independent. We then estimate changes in cancer and cardiovascular mortality since 1970. The bounds for the change in duration until death for either cause are fairly tight and suggest much larger improvements in cancer than previously estimated.  相似文献   
884.
We consider an intertemporal policy game between changing governments that differ in their attitudes towards a particular feature of market outcomes, exemplified with environmental pollution. When in power, a government will choose policy instruments and set strictness of regulation with a view to influencing the policy of future, possibly different, governments. We demonstrate that a “brown” government favours emission quotas over effluent taxes, as quotas establish property rights that are costly to reverse. Conversely, a “green” government prefers to regulate by taxes, in order to limit the incentives of future brown governments to ease regulations. Strategic behaviour tends to exaggerate policy differences (making green governments greener and brown governments browner) compared to when such strategic considerations were not an issue. (JEL: D81, D9, H23, L51, Q28, Q38)  相似文献   
885.
Habit formation has been proposed as a possible solution to the equity premium puzzle. This paper extends the class of models that support the habits explanation in order to account for heterogeneity in earnings, wealth, habits, and consumption. I find that habit formation does indeed increase the equity premium. However, contrary to earlier results, the habit hypothesis does not imply a price for risk as largeas the one measured in the data. There are three reasons for this. First, households in a habits economy modify their consumption/savings decision. Second, they modify their portfolio choice. These two changes in behavior diminish the consumption fluctuations faced by households. Third, the composition of the set of agents pricing risk in the economy changes so that relatively better self‐insured households end up pricing risk. (JEL: D52, G12, E21, C68)  相似文献   
886.
Customer behavior modeling has been gaining increasing attention in the operations management community. In this paper we review current models of customer behavior in the revenue management and auction literatures and suggest several future research directions.  相似文献   
887.
Abstract. This paper uses a representative sample of the Russian Federation, the Russian Longitudinal Monitoring Survey, to estimate the returns to education in this ex‐communist country. We tackle this classic issue in labor economics with the realistic expectation of obtaining results for Russia comparable in quality and reliability to those available in developed countries and other economies in transition. Using standard regression techniques we find that the returns to education in Russia are quite low compared with those reported in the literature on countries throughout the world, in almost no specification reaching higher than 5 per cent. Moreover, there is virtually no improvement in returns to education in the 1992–99 period, a result somewhat at odds with other studies using Russian data from similar time periods. When we instrument our main regressor using policy experiments from the 1960s, we find comparable results. We also perform a selectivity correction and discover even lower returns to education for men, although they become slightly higher for women. Additionally, we find extremely low returns to tenure, which can even become negative in certain specifications.  相似文献   
888.
We study auctions for a set of commonly‐ranked items where each buyer has unit demand. This setting has promising applications in areas such as keyword auctions in the search engine advertising industry, the sale of quality‐ranked raw materials, etc. An auction mechanism suitable for this setting is the simultaneous pooled auction (SPA), where each bidder simultaneously submits a single bid and is allocated an object based on the rank of his bid among all the bids. We study how to improve the seller's expected revenue by enforcing a reserve price in an SPA. We find that the use of an appropriate reserve price may significantly increase the seller's revenue, especially when the number of items for sale is relatively large compared to the number of participating bidders. One inherent problem in the SPA is that some bidders may incur ex post losses; that is, they pay more than what they value the received objects. We propose a tailored VCG mechanism that generates the same expected revenue as the SPA does, while bidders do not incur any ex post loss. We also discuss the potential applications of this research to keyword auctions.  相似文献   
889.
Abstract. The purpose of this paper is to study the intra‐household allocation of time to different household production activities using Swedish cross‐sectional household data. The Tobit model is rejected in favor of the Cragg model, suggesting that an empirical model has to take into consideration that allocation of time within the household is determined by two separate processes. Moreover, the results indicate that valuable information concerning the intra‐household allocation of time may be missing when household production is defined as the sum of different household activities, but there is no indication that statistically significant effects are wiped out in an aggregated analysis.  相似文献   
890.
Research has established that exposure to a combination of diagnostic (i.e., relevant) and nondiagnostic (i.e., irrelevant) information results in predictions that are more regressive than predictions based on diagnostic information (Hackenbrack, 1992; Hoffman and Patton, 1997). This phenomenon has been labeled the dilution effect (e.g., Tetlock and Boettger, 1989) and has been documented when individuals make predictions. This study tests for the dilution effect when small groups make predictions, and examines the effect of using a procedure designed to reduce the dilution effect. Results indicate that group predictions are influenced by nondiagnostic information in the same manner as are individual predictions, and allowing participants to rate the diagnosticity of information prior to making predictions does not reduce the dilution effect.  相似文献   
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