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991.
Although the state-space, unobserved component approach to forecasting has many advantages, it must be applied carefully in practice and should not be used in an uncritical, ‘black box’ fashion. In particular, such an approach to the modelling and forecasting of Spanish tourism data is inappropriate and leads to misleading conclusions, particularly in relation to the uncritical selection and use of explanatory regression variables.  相似文献   
992.
Many research studies have been done to explain the reasons for the tensions and failures observed in joint ventures between Japanese and Western multinational enterprises. These studies have identified, with various degrees of sophistication, the existence of cultural differences as a primary determinant of failure. Alternative explanations focus upon a transaction cost approach, emphasising opportunism and the danger of cheating in such strategic alliances. This paper synthesises the literature through the development of a new conceptual framework. This framework, which distinguishes between economic and cultural reasons for failure, provides a new lens to view the literature. It is demonstrated that the simple view of cultural incompatibility needs to be replaced by an awareness of the combined impact of cultural and economic forces on the viability of joint ventures between Japanese and Western firms.Lee T. Brown is a doctoral candidate in the Faculty of Management at the University of Toronto. Alan M. Rugman is Royal Bank Visiting Professor at the University of Alberta and Professor of International Business at the University of Toronto. Alain Verbeke is Assistant Professor of International Business at the University of Toronto. Helpful comments have been received from Nancy Adler, Mark Casson, Martin Evans, Tom Roehl, Mark Warner and Ken Watson.  相似文献   
993.
The single-equation approach has been commonly used in the studies of energy demand. However, as most of the data used in the energy demand model are unlikely to be stationary, this factor has to be taken into account when estimating the demand behavior. To overcome this problem, the authors have applied the cointegration and error-correction models to model Chinese coal consumption data. In order to contrast their performance with such traditional models as Hendry's general-to-specific approach, a forecast error comparison exercise has been conducted. In terms ofex post forecast errors, the Engle-Granger error correction model outperforms other chosen models. By using the Engle-Granger approach, it is possible to obtain important information about the behavior of coal demand in China.  相似文献   
994.
This paper presents four different patterns of technology development for small and medium sized companies in the machinery industry in a newly industrializing country, Korea. These four patterns are validated through indepth case studies. The case studies suggest that technology development patterns evolve according to firm size and the level of technological capability. In addition, the importance of non-formal methods of technology acquisition, technology accumulation, and business/technology policy for efficient technology development is also shown in this study. For the generalization of the findings, more extensive study in various industries and international comparative studies are needed.  相似文献   
995.
This paper addresses two issues. The first is whether demographic change was plausibly responsible for the run‐up in stock prices over the last decade, and whether an attempt by the baby boom cohort to cash out of its investments in the period 2010–2030 might lead to an “asset meltdown”. The second issue is whether the rise in dependency that will accompany the retirement of the baby‐boom cohort calls for an increase in national saving. We analyze these issues using a forward‐looking macro‐demographic model, and show that they are related via the existence of installation costs for capital. If such costs are sufficiently large, then demographics do have the power to affect stock prices, but “saving for America's old age” is less optimal. However, conventional estimates of capital installation costs are not large enough to explain large stock price movements in response to actual demographic change.  相似文献   
996.
Conclusion In the microeconomic portions of principles and intermediate macroeconomics, supply and demand analysis is presented as the truth. However, the simple Keynesian macroeconomic model virtually ignores market clearing, while the standard microeconomic model of supply and demand assumes perfect market clearing. Since hidden assumptions are a major source of confusion and misunderstanding between economists and the general public, students should be exposed to stock-flow analysis at the intermediate level as a separate or integrated chapter on supply and demand.  相似文献   
997.
In this article, we introduce Delta Boosting (DB) as a new member of the boosting family. Similar to the popular Gradient Boosting (GB), this new member is presented as a forward stagewise additive model that attempts to reduce the loss at each iteration by sequentially fitting a simple base learner to complement the running predictions. Instead of relying on the negative gradient, as is the case for GB, DB adopts a new measure called delta as the basis. Delta is defined as the loss minimizer at an observation level. We also show that DB is the optimal boosting member for a wide range of loss functions. The optimality is a consequence of DB solving for the split and adjustment simultaneously to maximize loss reduction at each iteration. In addition, we introduce an asymptotic version of DB that works well for all twice-differentiable strictly convex loss functions. This asymptotic behavior does not depend on the number of observations, but rather on a high number of iterations that can be augmented through common regularization techniques. We show that the basis in the asymptotic extension differs from the basis in GB only by a multiple of the second derivative of the log-likelihood. The multiple is considered to be a correction factor, one that corrects the bias toward the observations with high second derivatives in GB. When negative log-likelihood is used as the loss function, this correction can be interpreted as a credibility adjustment for the process variance. Simulation studies and real data application we conducted suggest that DB is a significant improvement over GB. The performance of the asymptotic version is less dramatic, but the improvement is still compelling. Like GB, DB provides a high transparency to users, and we can review the marginal influence of variables through relative importance charts and the partial dependence plots. We can also assess the overall model performance through evaluating the losses, lifts, and double lifts on the holdout sample.  相似文献   
998.
In this paper, we explore the features of a structural credit risk model wherein the firm value is driven by normal tempered stable (NTS) process belonging to the larger class of Lévy processes. For the purpose of comparability, the calibration to the term structure of a corporate bond credit spread is conducted under both NTS structural model and Merton structural model. We find that NTS structural model provides better fit for all credit ratings than Merton structural model. However, it is noticed that probabilities of default derived from the calibration of the term structure of a bond credit spread might be overestimated since the bond credit spread could contain non-default components such as illiquidity risk or asymmetric tax treatment. Hence, considering CDS spread as a reflection of the pure credit risk for the reference entity, we calibrate it in order to obtain more reasonable probability of default and obtain valid results in calibration of the market CDS spread with NTS structural model.  相似文献   
999.
We study whether the sealing of a defendant’s judicial records during a patent lawsuit filing correlates with the defendant’s level of competition and disclosure. Courts permit sealing of judicial records when competitive damage outweighs the public interest in access to documents and records. We find that defendants with sealed judicial records have higher research and development (R&D), lower industry sales concentration, and more references to competition in their annual reports than defendants without sealed judicial records. We observe faster mean reversion of return on net operating assets when courts seal defendant records. The results suggest that sealing relates to archival measures of competition. Finally, consistent with proprietary costs restraining disclosure, we find that defendants with sealed judicial records are less likely to issue management forecasts, file 8-Ks less frequently, and have longer and less readable 10-Ks.  相似文献   
1000.
Targets provide incentives for earnings management, and a longstanding question is whether earnings management is undertaken opportunistically or to communicate private information about future firm value. To discriminate between these motivations, I follow analytical research showing that an increase in competition through a large decrease in tariffs disciplines managers and better aligns their interests with those of shareholders. Thus, if earnings management reflects managerial opportunism, then an increase in competition will decrease earnings management; and if it signals future performance expectations, then an increase in competition will increase earnings management. Consistent with earnings management indicating managerial opportunism, I show that an increase in competition decreases real earnings management to avoid reporting negative earnings or a negative change in earnings. In addition, by showing that the lessening of trade barriers through import tariff reductions reduces the use of real earnings management to meet or beat earnings targets, I provide evidence on the role of macroeconomic conditions as a determinant of earnings quality.  相似文献   
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