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951.
Modeling Methods for Discrete Choice Analysis   总被引:2,自引:3,他引:2  
This paper introduces new forms, sampling and estimation approaches fordiscrete choice models. The new models include behavioral specifications oflatent class choice models, multinomial probit, hybrid logit, andnon-parametric methods. Recent contributions also include new specializedchoice based sample designs that permit greater efficiency in datacollection. Finally, the paper describes recent developments in the use ofsimulation methods for model estimation. These developments are designed toallow the applications of discrete choice models to a wider variety ofdiscrete choice problems.  相似文献   
952.
This article examines how to account for the welfare effects of carbon dioxide emissions, using the historical experiences of Britain and the USA from the onset of the industrial revolution to the present. While a single country might isolate itself from the detrimental effects of global warming in the short run, in the long all countries are unable to free ride. Thus, we support the use of a single global price for carbon dioxide emissions. The calculated price should decrease as we move back in time to take into account that carbon dioxide is a stock pollutant, and that one unit added to the present large stock is likely to cause more damage than a unit emitted under the lower concentration levels in the past. We incorporate the annual costs of British and US carbon emissions into genuine savings, and calculate the accumulated costs of their carbon dioxide emissions. Enlarging the scope and calculating the cumulative cost of carbon dioxide from the four largest emitters gives new insights into the question of who is responsible for climate change.  相似文献   
953.
Objectives:

Knee cartilage damage is a common cause of referral for orthopedic surgery. Treatment aims to reduce pain and symptoms by repairing cartilage. Microfracture, the current standard of care, yields good short-term clinical outcomes; however, treatment might fail after 2–3 years. A Chitosan-Beta glycerolphosphate-based medical device (BST-CarGel) is used as an adjunct to microfracture and demonstrates improvements in quantity and quality of repaired tissue, potentially reducing the risk of treatment failure. This study aimed to establish the economic value of BST-CarGel vs microfracture alone in knee cartilage repair from the societal perspective, using Germany as the reference market.

Methods:

A decision tree with a 20-year time-horizon was constructed, in which undesirable clinical events were inferred following initial surgery. These events consisted of pain management, surgery, and total knee replacement. Clinical outcomes were taken from the pivotal clinical trial, supplemented by other literature. Data and assumptions were validated by a Delphi panel. All relevant resource use and costs for procedures and events were considered.

Results:

In a group of patients with all lesion sizes, the model inferred that BST-CarGel yields a positive return on investment at year 4 (with 20-year cumulative cost savings of €6448). Reducing the incremental risk of treatment failure gap between the device and microfracture by 25–50% does not alter this conclusion. Cost savings are greatest for patients with large lesions; results for patients with small lesions are more modest.

Limitations:

Clinical evidence for microfracture and other interventions varies in quality. Comparative long-term data are lacking. The comparison is limited to microfracture and looks only at costs without considering quality-of-life.

Conclusion:

BST-CarGel potentially represents a cost-saving alternative for patients with knee cartilage injury by reducing the risk of clinical events through regeneration of chondral tissue with hyaline characteristics. Since the burden of this condition is high, both to the patient and society, an effective and economically viable alternative is of importance.  相似文献   

954.
Manufacturing is now a national strategy for many countries to combat slow economic growth, and positively viewed with the current trend of onshoring foreign manufacturing operations. We develop a cross-country regression model that predicts manufacturing employment as a function of population growth, foreign direct investment, and purchasing power parity. Results through the year 2100 suggest that manufacturing is trending toward a global equilibrium with higher levels of manufacturing outputs but much lower levels of manufacturing employment. The reason is that countries tend to evolve from having little manufacturing to commodity manufacturing at large scale and low wages. As infrastructure and human capital develop, there is the tendency to pursue advanced manufacturing in support of higher valued goods. The manufacture of commodity products is then outsourced to those countries with lower costs justified by their less-developed infrastructure and human capital, and so the virtuous cycle continues. While this model suggests that current efforts in revitalization of domestic manufacturing would lead to an increase in wealth in the United States, the bad news is that these gains are unlikely to be sustainable in the long term. However, the good news is that manufacturing acts as a rising tide that raises all nations and our global quality of life.  相似文献   
955.
Marketing thrives on secrets, yet surprisingly little formal attention has been paid to how the marketing of secrecy and the secrecy of marketing can play a significant role in contemporary organizations. We draw upon the fields of organizational studies, psychology, and marketing to develop a typology of secrets that reflects their marketing value and their knowledge value. Marketing secrets can have value to the firm (strategic value), to the customer (marketing value), or to both parties. Based on these two dimensions, we identify four different types of marketing secrets: (1) appealing secrets have high strategic value, as well as high marketing value; (2) mythical secrets mean little to the firm but a lot to the customer; (3) plain secrets are critical to the firm but are irrelevant to customers; and (4) weak secrets have neither strategic value nor marketing value. Our typology enables academics to formulate research questions regarding secrecy in marketing, and serves as a guide for practitioners in the construction of strategies that can exploit the strategic value of secrets by ‘romancing’ them, and increase their knowledge value by ‘educating’ the secrets.  相似文献   
956.
There is a large empirical literature on the effect of aggregate inflation on both price-level dispersion (relative price variability, RPV) and inflation rate dispersion (relative inflation variability, RIV) across goods or locations. Early empirical work of RIV has an explicit theoretical foundation in signal-extraction models. However, recent empirical work on RPV has produced results inconsistent with signal-extraction models. In particular, while RIV is increasing in the absolute value of inflation shocks, RPV is a negative monotonic function of inflation shocks. We show that consumer search theory offers a potential explanation for these apparently contradictory observations.  相似文献   
957.
We combine natural science modelling and valuation techniques to present economic analyses of a variety of land use change scenarios generated for the UK National Ecosystem Assessment. Specifically, the agricultural, greenhouse gas, recreational and urban greenspace impacts of the envisioned land use changes are valued. Particular attention is given to the incorporation of spatial variation in the natural environment and to addressing issues such as biodiversity impacts where reliable values are not available. Results show that the incorporation of ecosystem services and their values within analyses can substantially change decisions.  相似文献   
958.
We analytically assess the effects of changes in longevity on the interest rate, the consumption-savings behavior, and the optimal retirement decision within a dynamic general equilibrium setting. We derive a simple sufficient condition for which the optimal retirement age always increases with life expectancy. Numerical assessment reveals that for realistic parameter values that reflect the situation in industrialized countries, the optimal retirement age indeed increases with life expectancy and the sufficient condition tends to be fulfilled. Together with the fact that the actual retirement age did not increase in industrialized countries over the last decades, while there have been large improvements in longevity, this leads us to conclude that strong monetary and institutional incentives for early retirement exist and these counteract the effects of increasing life expectancy. Our policy conclusion is that the retirement age should be partially linked to life expectancy and that incentives for early retirement should be removed.  相似文献   
959.
We analyze an all-pay group contest in which individual members’ efforts are aggregated via the best-shot technology and the prize is a public good for the winning group. The interplay of within-group free-riding and across-group competition allows for a wide variety of equilibria, according to how well groups overcome internal free-riding. In contrast with the existing literature, we derive equilibria of a symmetric model in which multiple agents per group are active. Our findings differ qualitatively from those of the individualistic all-pay auction: rents are not necessarily dissipated in equilibrium, total expected efforts vary across equilibria, and participation is expected to be greater. Moreover, equilibria with greater symmetry of behavior within a group are shown to have more “wasted” effort but also greater payoffs as overall efforts are lower. In contrast to standard economic intuition, free-riding can be beneficial for players as it reduces competition among groups. Examples of asymmetric group contests are also studied.  相似文献   
960.
This article considers the impact of ambiguity in strategic situations. It extends the existing literature on games with ambiguity‐averse players by allowing for optimistic responses to ambiguity. We use the CEU model of ambiguity with a class of capacities introduced by Jaffrray and Philippe (Mathematics of Operations Research 22 (1997), 165–85), which allows us to distinguish ambiguity from ambiguity‐attitude, and propose a new solution concept, equilibrium under ambiguity (EUA), for players who may be characterized by ambiguity‐preference. Applying EUA, we study comparative statics of changes in ambiguity‐attitude in games with strategic complements. This extends work in Eichberger and Kelsey (Journal of Economic Theory 106 (2002), 436–66) on the effects of increasing ambiguity if players are ambiguity averse.  相似文献   
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