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971.
Using two large hedge fund databases, this paper empirically tests the presence and significance of a cross-sectional relation between hedge fund returns and value at risk (VaR). The univariate and bivariate portfolio-level analyses as well as the fund-level regression results indicate a significantly positive relation between VaR and the cross-section of expected returns on live funds. During the period of January 1995 to December 2003, the live funds with high VaR outperform those with low VaR by an annual return difference of 9%. This risk-return tradeoff holds even after controlling for age, size, and liquidity factors. Furthermore, the risk profile of defunct funds is found to be different from that of live funds. The relation between downside risk and expected return is found to be negative for defunct funds because taking high risk by these funds can wipe out fund capital, and hence they become defunct. Meanwhile, voluntary closure makes some well performed funds with large assets and low risk fall into the defunct category. Hence, the risk-return relation for defunct funds is more complicated than what implies by survival. We demonstrate how to distinguish live funds from defunct funds on an ex ante basis. A trading rule based on buying the expected to live funds and selling the expected to disappear funds provides an annual profit of 8–10% depending on the investment horizons. 相似文献
972.
A buyer’s technical knowledge may increase the efficiency of its supplier. Suppliers, however, frequently maintain relationships
with additional buyers. Knowledge disclosure then bears the risk of benefiting one’s own rival due to opportunistic knowledge
transmission through the common supplier. We show that in one-shot relationships no knowledge disclosure takes place because
the supplier has an incentive to transmit and, anticipating that, buyers refuse to disclose any of their knowledge. In repeated
relationships knowledge disclosure is stabilized by larger technological proximity between buyers and suppliers and destabilized
by the absolute value of the knowledge.
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978.
G. M. Dobrov 《R&D Management》1978,8(S1):133-149
Mankind's prospects both for finding new types of resources and for ensuring efficiency in resource utilization and substitution depend upon our success or failure in solving the problems of organizing and managing technological systems. A generalized scheme describing interaction among the basic elements of the management of national science and technology (ST) activity is outlined, and one particular element isolated for detailed examination: the system analysis and systematic assessment of new technology (SANT). The role of SANT in the context of decision-making in the management of ST progress is described, together with the methodological arsenal available. No one technique is universally good; the problem is to find systematic means of using a selection of methods which mutually compensate for each other's weaknesses. Further difficulties are encountered over the non-comparability or absence of initial data, and a framework for viewing the various classes of data available and making use of them is outlined. Examples are given of the practical application of SANT to problems such as the development of a macro-model., for the planning of national ST policy, and a model of technological change in the area of the science, technology, and exploitation of computers. A system is described which handles the data stores and information flows necessary for performing SANT routines. 相似文献
979.
We explore the effects of uncertainty on a firm that can respond by modifying its investment or production schedule (or both simultaneously) to variations in output price. Investment may increase capacity and/or reduce costs. We consider a firm with finite resources.Our model uses option theory instead of the more traditional net present value framework. One of the early papers using this approach is Brennan and Schwartz (1985) in which an investment project to extract a finite natural resource is valued. In that paper, the value of the firm is a function of two state variables, the finite resource to be extracted (output to be produced in the future) and the commodity spot price. In order to maximize firm value, the manager can respond by modifying one control variable, the production level. In our model we handle instead three state variables (spot price, resources, accumulated investment) and two control variables (production rate and investment rate), and solve numerically.We obtain both the value and the optimal policy of a firm that has investment projects that increase capacity and/or reduce costs and illustrate optimal policies as resources and available investments decrease over the life of the firm. Firms may start by only investing, then invest and produce, to end only producing.We thank Scott Wo, the referee and the editor for their comments and suggestions. Cortázar and Lowener acknowledge the financial support from FONDECYT and FONDER. 相似文献
980.
Stephen R. Foerster G. Andrew Karolyi 《Journal of International Financial Markets, Institutions & Money》1998,8(3-4)
We use transaction data for Toronto Stock Exchange (TSE) listed stocks to examine the impact on trading costs of the decision to interlist on a US exchange. We measure trading costs using both ‘posted’ bid-ask spreads and ‘effective’ bid-ask spreads that measure actual transaction prices relative to standing bid-ask quotes. After controlling for price level, trade size and trading volume effects, we find that overall posted and effective spreads in the domestic (TSE) market decrease subsequent to the interlisting. However, the decrease in trading costs is concentrated in those TSE stocks that experience a significant shift of total trading volume (TSE and US) to the US exchange after listing. We interpret this result in the context of theories of multimarket trading as a competitive response by TSE market makers to the additional presence of US market makers. 相似文献