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41.
In this paper, using daily data for six major international stock market indexes and a modified EGARCH specification, the links between stock market returns, volatility and trading volume are investigated in a new nonlinear conditional variance framework with multiple regimes and volume effects. Volatility forecast comparisons, using the Harvey-Newbold test for multiple forecasts encompassing, seem to demonstrate that the MSV-EGARCH complex threshold structure is able to correctly fit GARCH-type dynamics of the series under study and dominates competing standard asymmetric models in several of the considered stock indexes.
José Dias CurtoEmail:
  相似文献   
42.
This article is geared toward shedding some more light on what may be the next space race and its contours.Space flight is undoubtedly a human achievement of the second half of the 20th century, and probably the most audacious one of the past century. The space race started suddenly in the 1950s and has grown explosively during the following two decades, but decreased steadily after the 1970s. After the 1990s, however, we have seen a shy rebirth of space-related activities, when many other actors (states) entered the stage, adding up to the agonizing role of the two-actor piece that we have witnessed during the so-called Cold War.The opening years of the 21st century provided a more complex narrative for space exploration. At the start of the new millennium a new technosphere [1] emerged, dominated by what is used to be called as the Information and Communications Technologies (ICT), with the Internet playing the leading role among the bandwagon of technological novelties that appeared during the twilight of space activities. In despite of the fact that artificial satellites represent the very backbone of the global communications system, space activities seem to play a secondary role amidst the apparently accelerated rate of change concerning the technological systems of the present technosphere. But, as it is demonstrated in this paper, things are changing, and very probably a renewed space race will unfold in the coming decades.A question may be placed: what happened? Why the Earth stood still with regard to the race toward the cosmos? Answer: futurists, even prestigious ones like Herman Kahn and Arthur Clarke, did not consider the existence of socioeconomic long waves (Kondratieff waves, or K-waves for short) with their two decades long economic downturn, which has contributed to the deceleration of space-related activities.Analyzing the worldwide evolving scenario of space-related activities during the last eighty years under the framework of the succeeding K-waves and applying some technological forecasting tools, namely the logistic analysis, technological surveillance and intensive data mining, scrutinizing more than 7500 events occurred in the period 1930–2010 related with space activities, it is demonstrated that the space race like the one that we have witnessed until now is a natural growth process that has saturated at the dawn of this century. The same analysis demonstrates that a new growth process in this field might be nowadays under way with contours very different from that imagined by futurists and science fiction writers sixty years ago. Also the main trends in the usage of launching vehicles and satellites are framed and discussed in this paper.  相似文献   
43.
The trade literature has long discussed the existence of some benefits attributed to exporting (learning-by-exporting), among others, the improvement in survival chances. This paper examines whether exporting SMEs enjoy better survival prospects than non-exporting SMEs. We investigate the determinants of survival of exporting and non-exporting SMEs and explore whether the exporting behaviour plays a significant role in explaining their probability of exit. For this purpose, we estimate discrete time proportional hazard models that account for unobserved individual heterogeneity. The dataset is a sample of Spanish manufacturing SMEs drawn from the Encuesta sobre Estrategias Empresariales (ESEE) for 1990–2002. After controlling for firm, industry and economy characteristics, we find evidence supporting the existence of a sizeable “surviving-by-exporting” effect. That is, exporting SMEs face a significantly lower probability of failure than non-exporters.  相似文献   
44.
We study individually rational rules to be used to allot, among a group of agents, a perfectly divisible good that is freely available only in whole units. A rule is individually rational if, at each preference profile, each agent finds that her allotment is at least as good as any whole unit of the good. We study and characterize two individually rational and efficient families of rules, whenever agents' preferences are symmetric single-peaked on the set of possible allotments. Rules in the two families are in addition envy-free, but they differ on whether envy-freeness is considered on losses or on awards. Our main result states that (a) the family of constrained equal losses rules coincides with the class of all individually rational and efficient rules that satisfy justified envy-freeness on losses and (b) the family of constrained equal awards rules coincides with the class of all individually rational and efficient rules that satisfy envy-freeness on awards.  相似文献   
45.
Cuestas  Juan Carlos  Monfort  Mercedes  Ordóñez  Javier 《Empirica》2021,48(4):1113-1129
Empirica - In March 2010, the European Commission launched the Europe 2020 strategy ‘for smart, sustainable and inclusive growth’ in the EU. Education is a major pillar of the Europe...  相似文献   
46.

Peru is the second-largest producer and exporter of copper in the world. This paper proposes a novel approach to assess short-run and long-run effects of copper on Peru’s recent economic growth. Annual data over the 2014–2018 period were used to calculate a Mining Contribution Index (MCI). An institutional quality indicator of the World Competitiveness Index of the World Economic Forum measured the dependence of Peruvian economic growth on mining and the quality of its institutions, respectively. Then, monthly data during the period 2005–2018 were used to run vector autoregressive (VAR) and vector error correction (VEC) models to measure copper’s effects on the country’s economy over time. VAR-VEC models included copper production, exports, international price, investment, taxes paid by producing companies, and Peru’s gross domestic product (GDP). Stationarity and causality of variables were verified with the Augmented Dickey-Fuller and Granger tests, respectively. Due to the presence of non-stationary variables, a VEC model was implemented to forecast short- and long-run effects. The main results show that real GDP responds to copper output and other related explanatory variables differently, depending upon the instrument applied. Peruvian GDP has increased dependence on copper mining. The quality of its institutions could explain the presence of Dutch Disease or resource curse theory. Short- and long-run effects of copper output on GDP were generally statistically non-significant. GDP was statistically significant in relation to other mining variables, such as copper exports and the international price of copper.

  相似文献   
47.
Technological innovations have been investigated by means of substitution and diffusion as well as evolution models, each of them dealing with different aspects of the innovation problem. In this paper we follow the well known research traditions on self-organisation models of complex systems. For the first time in the literature we show the existence of a specific niche effect, which may occur in the first stage of establishment of a new technology. Using a stochastic Master equation approach, we obtain analytical expressions for the survival probabilities of a new technology in smaller or larger ensembles. As a main result we demonstrate how a hyperselection situation might be removed in a stochastic picture and thresholds against the prevailing of a new technology in a step-by-step process can be overcome.  相似文献   
48.
Summary For a class of infinite signaling games, the perfect Bayesian equilibrium strategies of finite approximating games converge to equilibrium strategies of the infinite game. This proves the existence of perfect Bayesian equilibrium for that class of games. It is well known that in general, equilibria may not exist in infinite signaling games.I am very grateful to Karl Iorio with whom I derived most of the results in this paper. I am solely responsible for any remaining errors. I am also grateful to Robert Anderson, Debra Aron, Eddie Dekel, Raymond Deneckere, Michael Kirscheneiter, Steven Matthews, Roger Myerson, Daniel Vincent and Robert Weber for comments on previous drafts of this paper.  相似文献   
49.
This study examines the impact of trade on Cuban growth during different commercial policy regimes spanning the period from 1960 up to 2004, encompassing two essential economic structural transformations: the Cuban revolution and the fall of the Berlin Wall. For this purpose, the Granger causality is used by means of the modified Wald test for augmented‐level vector autoregressive model with integrated and cointegrated processes introduced by Toda and Yamamoto (1995) and Dolado and Lutekepohl (1996) . We show an import‐led growth hypothesis during the Soviet‐oriented pattern that is rejected after 1990, when exports are not only responsive to growth expansion but also to imports’ behaviour.  相似文献   
50.
While the biofouler Corbicula fluminea (Müller, 1774) is known to cause great economic losses in North America, studies reporting the problem in Europe are much scarcer. This paper explores the industrial effects of the species in Portugal, the gateway by which the bivalve entered Europe around 30 years ago. National waterworks, major power stations, cement plants, pulp and paper mills and irrigation systems were surveyed. The industrial impacts of the pest were shown to remain relatively mild; irrigation systems are those that seem to be facing more significant economic losses due to infestation. Possible reasons for the apparent discrepancy between this result and the species dispersal in natural ecosystems are discussed, and recommendations on adequate responses to the latent threat are provided. This study may assist the implementation of integrated pest management policies in countries at risk of invasion or recently invaded, and contribute to an understanding of the species’ progression in industrial environments.  相似文献   
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