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71.
For valuing derivatives and other assets in securities and commodities markets, arbitrage pricing theory has been a major approach for decades. This paper derives fundamental arbitrage pricing results in finite dimensions in a simple unified framework using Tucker’s theorem of the alternative. Frictionless results, that is perfect market results, plus imperfect market results such as those with dividends, periodic interest payments, transaction costs, different interest rates for lending and borrowing, shorting costs and constrained short selling are presented. While the results are mostly known and appear in various places, our contribution is to present them in a coherent and comprehensive fashion with very simple proofs. The analysis yields a simple procedure to prove new results and some are presented for cases with imperfect market frictions.  相似文献   
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The emergence of macroprudential policies, implemented by central banks as a means of promoting financial stability, has raised many questions regarding the interaction between monetary and macroprudential policies. Given the limited number of studies available, this paper sheds light on this issue by providing a critical and systematic review of the literature. To this end, we divide the theoretical and empirical studies into two broad channels of borrowers – consisting of the cost of funds and the collateral constraint – and financial intermediaries – consisting of risk‐taking and payment systems. In spite of the existing ambiguity surrounding coordination issues between monetary and macroprudential policies, it is argued that monetary policy alone is not sufficient to maintain macroeconomic and financial stability. Hence, macroprudential policies are needed to supplement monetary. In addition, we find that the role of the exchange rate is critical in the implementation of monetary and macroprudential policies in emerging markets, while volatile capital flows pose another challenge. In so far as how the arrangement of monetary and macroprudential policies varies across countries, key theoretical and policy implications have been identified.  相似文献   
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Abstract

Aims: To determine the clinical effectiveness and safety of venous thromboembolism (VTE) prophylaxis using US- and Europe-approved anticoagulants relative to extended-duration VTE prophylaxis with betrixaban. Low molecular weight heparins (LMWHs), unfractionated heparin (UFH), fondaparinux sodium and placebo were each compared to betrixaban, as standard-duration VTE prophylaxis for hospitalized, non-surgical patients with acute medical illness at risk of VTE.

Materials and methods: A systematic literature review was conducted up to June 2019 to identify randomized controlled trials (RCTs) of VTE prophylaxis in hospitalized, non-surgical patients with acute medical illness at risk of VTE. Studies that reported the occurrence of VTE events (including death) and, where possible, major bleeding, from treatment initiation to 20–50?days thereafter were retrieved and extracted. A Bayesian fixed effect network meta-analysis was used to estimate efficacy and safety of betrixaban compared with standard-duration VTE prophylaxis.

Results: Seven RCTs were analyzed which compared betrixaban, LMWHs, UFH, fondaparinux sodium, or placebo. There were significantly higher odds (median odds [95% credible interval]) of VTE with LMWHs (1.38 [1.12–1.70]), UFH (1.60 [1.05–2.46]), and placebo (2.37 [1.55–3.66]) compared with betrixaban. There were significantly higher odds of VTE-related death with placebo (7.76 [2.14–34.40]) compared with betrixaban. No significant differences were observed for the odds of major bleeding with all comparators, VTE-related death with any active standard-duration VTE prophylaxis, or of VTE with fondaparinux sodium, compared with betrixaban.

Limitations and conclusions: In this indirect comparison, betrixaban was shown to be an effective regimen with relative benefits compared with LMWHs and UFH. This indicates that betrixaban could reduce the burden of VTE in at-risk hospitalized patients with acute medical illness who need extended prophylaxis, though without direct comparative evidence, stronger conclusions cannot be drawn.  相似文献   
76.
Productivity slowdown plays a prominent role in the build-up of the euro area crisis. This phenomenon affected member countries asymmetrically, causing divergence in their productivity trends. Recent research traces this divergence back to monetary integration. After reviewing the arguments that link real “disintegration” of the euro area to its monetary integration, we assess them empirically by modelling the evolution of labour productivity using a panel of sectorial data. The results indicate that monetary unification may actually have fostered divergence in productivity trends, and suggest some economic policy measures that could prevent further divergence.  相似文献   
77.
Throughout the developing world, many water distribution systems are unreliable. As a result, it becomes necessary for each household to store its own water as a hedge against this uncertainty. Since arrivals of water are not synchronized across households, serious distributional inefficiencies arise. We develop a model describing the optimal intertemporal depletion of each household's private water storage if it is uncertain when water will next arrive to replenish supplies. The model is calibrated using survey data from Mexico City, a city where many households store water in sealed rooftop tanks known as tinacos. The calibrated model is used to evaluate the potential welfare gains that would occur if alternative modes of water provision were implemented. We estimate that most of the potential distributional inefficiencies can be eliminated simply by making the frequency of deliveries the same across households which now face haphazard deliveries. This would require neither costly investments in infrastructure nor price increases.  相似文献   
78.
Can economically efficient outcomes be obtained and sustained in the absence of externally enforced property rights? We study the evolutionary properties of a game that exhibits two well-defined Nash equilibria: one generates an inefficient outcome while the other set generates an efficient outcome supported by the potential for retaliation. Although standard forward-looking refinements eliminate the efficient equilibrium, neither equilibrium type satisfies strict evolutionary stability criteria. However, both types of equilibrium define strategies that are neutrally stable, which makes them vulnerable to drift in dynamic environments. We conduct computer simulation experiments in which players learn adaptively via a tournament selection mechanism called sophisticated experimentation. Our simulations demonstrate that while the system spends a disproportionately high proportion of time in the inefficient equilibrium set, the efficient equilibrium is pervasive as the system drifts back and forth between the equilibrium sets, never settling on one or the other.  相似文献   
79.
The extent of the demographic changes is dramatic especially in some Asian and European countries. This paper investigates the effect of aging on global asset markets and asset returns, focusing on markets for productive capital, and especially on interactions between European and Asian economic development. Aging has complex effects on the markets for real capital. If elderly people save less than younger people, interest rates will increase. At the same time, however, the younger generation becomes smaller, which reduces the demand for new investment. The equilibrium effect is thus uncertain. Our multicountry computational equilibrium model delivers a subtle picture: there will be some decline in the return from productive capital, but it is relatively small. We find noticeable interaction effects between labor market and pension reforms in Europe on the one hand, and the demographic and economic developments in Asia, especially India and China, on the other hand.  相似文献   
80.
This note formalizes bias and inconsistency results for ordinary least squares (OLS) on the linear probability model and provides sufficient conditions for unbiasedness and consistency to hold. The conditions suggest that a “trimming estimator” may reduce OLS bias.  相似文献   
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