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991.
Homeownership rates equal the number of households that own homes divided by the number of households in the population. Differences in the propensity to form a household, therefore, may contribute to changes in homeownership rates over time in addition to long-standing racial gaps in homeownership. We examine these issues on an age-specific basis using data from the 1970 to 2000 public use microsamples of the decennial census. Results indicate that lower headship rates tend to reduce homeownership rates. This pattern is most notable for individuals in their early and mid 20s. For these individuals, declining headship rates between 1970 and 2000 reduced homeownership rates by three to five percentage points. Moreover, 2000 African American headship rates narrow white–black gaps in homeownership by roughly three percentage points, whereas 2000 Hispanic headship rates widen white–Hispanic gaps in homeownership by two to three percentage points. Thus, controlling for differences in headship behavior, white–black homeownership gaps are somewhat more severe than previously recognized, but the reverse is true for white–Hispanic gaps.  相似文献   
992.
Given industry competitiveness, how do firms' new product development (NPD) process designs differ when responding to an innovation mandate? How do NPD design elements differ across firms when implementing NPD processes? These design elements are strategic business unit (SBU) senior management involvement, business case content, customer interactions, and cross‐functional integration. What are the consequences of different combinations of NPD process design elements for innovation productivity? We explore these questions via a collective case study of newly implemented NPD process designs at three different SBUs of a major US‐based international conglomerate, 1 year after receiving the mandate to grow through innovation. Our analysis suggests that industry competitiveness and firm characteristics influence the NPD process design as SBUs employ distinct combinations of NPD design elements. The differential emphasis on design elements leads to variation in process design and divergence in innovation productivity.  相似文献   
993.
This paper suggests an innovative measure of structural relief obtained in a typical Section 7 settlement. The fraction of competitive overlap subject to divestiture as a condition of the settlement is modeled as a function of merger-specific efficiencies, the proportion of the deal held “hostage” to antitrust review, the merger’s anticompetitive potential, and other factors. The model is applied to data on 86 recent Justice Department cases covering the period 1990–2003 and to the subsample of 1990s cases. All data are collected from publicly available documents only. The government is found to secure larger divestitures when the cost to the acquirer of delaying the settlement is high. The resulting estimates are used to predict several out-of-sample observations. I would like to thank the General Editor and two anonymous referees for many helpful suggestions on earlier drafts of this paper. The remaining errors are mine.  相似文献   
994.
There has been a shift from transactional to relational exchange and relationship marketing both in the business to business and professional services contexts. This paper seeks to explore the manner in which personal relationships affect the process and outcomes of purchasing of professional business services. Specifically, it focuses on the role of the professional service providers as boundary spanners in the formation of personal relationships. These personal relationships constitute the underlying basis of long-term relationships between the purchasing and provider organizations in such complex service settings. The findings of this study demonstrate that the manner in which the boundary spanners cultivate relationships support the concept of relationship specific tasks. It extends this conception by use of the data to outline the chronological process over time Understanding the roles, function, and ultimately importance, of these relationships facilitates the identification and development of appropriate strategies to manage these relationships.  相似文献   
995.
Combining longitudinal field research and executive experience, we propose that corporate longevity depends on matching cycles of autonomous and induced strategy processes to different forms of strategic dynamics, and that the role of alert strategic leadership is to appropriately balance the induced and autonomous processes throughout these cycles. We also propose that such strategic leadership is the means through which leadership style exerts its influence on corporate longevity. Our findings can be related to organizational research on structural inertia, learning and adaptation, as well as to formal theories of complex adaptive systems. They also contribute to resolving the seeming contradiction between a study of corporations that attributes exceptional long‐term success to leadership style, and the more common proposition that strategy is the determinant of long‐term performance. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
996.
This paper determines the effect of estimation risk on optimal portfolio choice under uncertainty. In most realistic problems, the parameters of return distributions are unknown and are estimated using available economic data. Traditional analysis neglects estimation risk by treating the estimated parameters as if they were the true parameters to determine the optimal choice under uncertainty. We show that for normally distributed returns and ‘non-informative’ or ‘invariant’ priors, the admissible set of portfolios taking the estimation uncertainty into account is identical to that given by traditional analysis. However, as a result of estimation risk, the optimal portfolio choice differs from that obtained by traditional analysis. For other plausible priors, the admissible set, and consequently the optimal choice, is shown to differ from that in traditional analysis.  相似文献   
997.
It is argued in this article that sub-Saharan Africa, given its present institutions and endowments of capital and technology, is already dangerously close to overpopulation. The rapid growth of its population projected for the next decades will greatly increase human misery and depress economic development. Specifically, rapid population growth will have disastrous effects on the region's ability to increase exports and provide people with food. There must be a search for new ways in which these effects could be mitigated. In sub-Saharan Africa fertility either continues to be very high or is increasing, in part due to some decline in traditional practices that reduce fertility, such as prolonged breastfeeding. This situation and the expectation of declining mortality imply that African population growth may increase further. Currently, population in sub-Saharan Africa is about half that of India and a third of China. There are 2 main reasons why reduced fertility in the next few decades is unlikely in sub-Saharan Africa as a whole: Africa has low literacy, high infant and child mortality, and low urbanization; and average African fertility rates may even increase for the next 20 years or so. The question that arises is what are the implications of continuing and rapid population growth for the African food supply. The region's cereal production is largely restricted to 4 grains, i.e., millet, sorghum, maize, and rice. The volume of grain production is less, by weight, than 60% of the production of roots and tubers. There are 2 main differences between the output of these crops in sub-Saharan Africa and the rest of the world: yields/hectare are lower in Africa than in elsewhere; and yields have generally been decreasing or largely constant in Africa. The low productivity has several causes. Today, population pressure has brought diminishing returns to traditional agriculture in much of the Sahel and the savanna, in parts of East Africa, Southern Africa, and parts of the West African forest belt. There is also the absence of the Green Revolution, i.e., the use of new high yielding seeds and new technologies in agriculture that has led to marked increases in yields in most other parts of the world. A totally different and more productive agriculture might evolve if African governments were to fundamentally change their vision. Existing production technology could allow substantial increases in the yields of many crops if some basic changes were made in the policies affecting agriculture. A way to achieve such change would be to make farming profitable. The effect of population growth in diminishing returns to agriculture also lends urgency to the need for family planning. Generally, population policy in Africa badly needs strengthening.  相似文献   
998.
999.
Abstract: The passage of California's Proposition 103 in November 1988 changed the State's regulatory structure for insurers from a competitive to a heavily regulated system. The six-year legal battle that followed resulted in several California Supreme Court and United States Supreme Court rulings and an ultimate implementation of rate roll backs on property-liability insurers on November 22, 1994. The study examines both property-liability and life insurers' returns. While only property-liability insurers are affected by the rale rollback and prior approval rate regulation, both life and property-liability insurers are affected by the proposition's other provisions. This paper examines the effect of successive changes on both types of insurance companies and analyzes the differential impact of the changes in regulatory structure.  相似文献   
1000.
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   
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