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91.
This paper reports an experiment designed to assess the effects of a rotation in the marginal cost curve on convergence in a repeated Cournot triopoly. Increasing the cost curve's slope both reduces the serially-undominated set to the Nash prediction, and increases the peakedness of earnings. We observe higher rates of Nash equilibrium play in the design with the steeper marginal cost schedule, but only when participants are also rematched after each decision. Examination of response patterns suggests that the treatment with a steeper marginal cost curve and with a re-matching of participants across periods induces the selection of Nash Consistent responses.  相似文献   
92.
We build on our earlier model of money in which bank liabilities circulate as a medium of exchange. We investigate optimal bank behavior and the resulting provision of liquidity under a range of central bank regulations. In our model, banks issue inside money under fractional reserves, facing the possibility of excess redemptions. Banks consider the float resulting from money creation and make reserve‐management decisions that affect aggregate liquidity conditions. Numerical examples demonstrate positive bank failure rates when returns to banking are low. Central bank interventions may improve banks' returns and welfare through a reduction in bank failure.  相似文献   
93.
We compare different contingent valuation question formats with each other and with observed behaviour for a non-monetary estimation task, the expected number of kilometers travelled by automobile. Open-ended questions, open-ended follow-up questions, dichotomous choice (DC) questions, and double-bound DC questions are included. The single and double-bound DC questions result in an estimated mean about twice as high as the actual value and the open-ended mean. The DC question overestimation seems to be due to an anchoring effect leading to yea-saying behaviour. Our results about the difference between DC questions and open-ended questions is consistent with the pattern observed in contingent valuations studies of the willingness to pay. Our results indicates that DC questions seem to be associated with a general overestimation problem that is present even for simple non-monetary estimation tasks.  相似文献   
94.
Multinomial Logit Model has analyzed the relationship between the frequency of visits to recreation areas and the motivational factors affecting the visits. Kastro Environment Preserving Site that is located in the Black Sea coast of Marmara region in Turkey, has been chosen as the site for this study. Kastro bay is a natural park that is visited only for recreational visits. The study has been conducted on a photogenic study group due to the proximity factor of Kastro bay close to Istanbul. Kastro bay is a popular recreational park due to its characteristic advantages such as a 200 m wide and approximately 2.5 km long beach and with its high quality vegetation. The vegetation type includes ash tree, oak tree, black pine, sand lily etc. Kastro bay is also the site for the Mediterranean seals (Monachus-monachus) which are at the level of extinction. Approximately 50,000 visitors visit the region during the months of July and August. It has been concluded that there is high direct correlation between the frequency of visits and the motivational factors. It has been determined that the visits are mostly based on the sea and the ecological tourism.Jel: O13, Q20, Q26, Q51, Q56, Q57  相似文献   
95.
We analyze how the market processes a signaling event by studying a sample of self-tender offers, events often viewed as signals of firm value. By examining changes in the degree of informed trading, we find asymmetric information costs fall at announcement, remain low throughout the event, and increase at offer expiration. By one month following expiration, informed trading returns to a level not significantly different from that prior to the offer. Higher risk firms have significantly larger declines in information asymmetry during the offer. Increases in information asymmetry persist one month following expiration for firms with lower pre-offer informed trading. (JEL G14, G32)  相似文献   
96.
Within a production function framework in which government spending produces public goods which enter firms production functions, empirical tests using time series data spanning eleven countries and thirty industries find both the scale and the composition of government consumption spending to affect the level and the rate of growth of total factor productivity at the industry level.Jel Classification: H50, D24  相似文献   
97.
One particularly vexing puzzle for economists and policymakers over the past several decades concerns the empirical significance of the theoretically predicted pollution haven hypothesis. While neoclassical theory and conventional wisdom both surmise that local economies will suffer deleterious effects from stricter environmental regulations, empirical studies have largely failed to validate such claims. This study utilizes the method of matching to show that the impact of stricter regulation is heterogeneous spatially, varying systematically based on location-specific attributes. Previous studies that assume a homogenous response may therefore inadvertently mask the overall impact of more stringent regulations by pooling unaffected and affected regions.JEL Classification: Q25, Q28, H00, L51, R1The authors wish to thank to Michael Crew, Anthony Heyes, an anonymous referee, Werner Antweiler, Randy Becker, Wayne Gray, Shelby Gerking, Michael Greenstone, Vern Henderson, and Arik Levinson. Participants at various university seminars and conferences also lent useful insights to this line of research.  相似文献   
98.
Summary. We seek to explain the economic volatility of the last 6 years, in particular the rapid expansion and contraction of the knowledge sectors. Our hypothesis is that these sectors amplify the business cycle due to their increasing returns to scale, growing faster than others in an upswing and contracting faster in a downswing. To test this hypothesis we postulate a general equilibrium model with two sectors: one with increasing returns that are external to the firm and endogenously determined - the knowledge sector - and the other with constant returns to scale. We introduce a new measure of volatility of output, a real beta, and derive a resolving equation, from which we prove that the increasing return sectors exhibit more volatility then other sectors. We validate the main results on US macro economic data of real GDP by industry (2-3 digits SIC codes) of the 1977-2001 period, and provide policy conclusions.Received: 18 March 2002, Revised: 16 February 2004, JEL Classification Numbers: D5, D58, E10, L50, L52, O38, O51.Correspondence to: Graciela Chichilnisky  相似文献   
99.
Using a small empirical model of inflation, output, and money estimated on U.S. data, we compare the relative performance of monetary targeting and inflation targeting. The results show monetary targeting to be quite inefficient, yielding both higher inflation and output variability. This is true even with a nonstochastic money demand formulation. Our results are also robust to using a P∗ model of inflation. Therefore, in these popular frameworks, there is no support for the prominent role given to money growth in the Eurosystem's monetary policy strategy.  相似文献   
100.
Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

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