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71.
Farmland for tomorrow in densely populated areas   总被引:1,自引:0,他引:1  
The paper describes the results of a research that aimed to come up with a well structured method to estimate future farmland requirements in densely populated areas. By using in depth interviews, scenario analysis and strategic orientation rounds, a method is developed to support policy optimization and to explore alternative future developments. The method is applied to the case of agriculture in the Flemish part of Belgium to show the feasibility of the model and to provide input for the discussion among policy makers in Flanders. The research results can be used by policy makers to build a new Spatial Plan Flanders for the period 2007–2013.  相似文献   
72.
We focus on determining the impacts of government programs on farms’ technical inefficiency levels. We use Kumbhakar's stochastic frontier model that accounts for both production risks and risk preferences. Our theoretical framework shows that decoupled government transfers are likely to increase (decrease) DARA (IARA) farmers’ production inefficiencies if variable inputs are risk decreasing. However, the impacts of decoupled payments cannot be anticipated if variable inputs are risk increasing. We use farm‐level data collected in Kansas to illustrate the model.  相似文献   
73.
The univariate statistical properties of agricultural price series need to be examined as a first step in the analysis of price transmission mechanisms. However, in the case of weekly price series, increasingly available, the testing procedures usually applied in this step are not suitable to deal with evolving seasonal effects. In this study, a method of testing for seasonal unit roots in weekly series of agricultural prices is described. When the deterministic seasonal component does not remain constant over time, the restricted evolving spline model (RESM) is shown to be a useful parametric formulation to capture the deterministic seasonal pattern. Therefore, the RESM model should be included as a deterministic component in auxiliary regression for unit root tests at seasonal frequencies. This proposal is applied to three weekly series of Canary Islands banana prices. From the standard seasonal unit root tests, the null hypothesis is failed to be rejected at the 5% or 10% significance level at some seasonal frequencies for each one of the series. Once critical values are obtained by simulation exercises when the RESM model is included, the hypotheses of unit root are rejected at each one of the seasonal frequencies for all of the three series.  相似文献   
74.
The FARC, which used to be Colombia's main guerrilla force and is now in the midst of a peace process, was to a great extent a feminized group. This paper discusses why it recruited so many women, and why it recruited them as combatants. We suggest that only when the FARC adopted a highly hierarchical, self‐contained, and militaristic organizational blueprint did it get involved in the massive recruitment of women as combatants. We discuss the way in which organizational mechanisms and ideology interacted to produce such an outcome, and how this interaction marked both the organization and the trajectories of the women who joined it.  相似文献   
75.
Distance functions are increasingly being augmented, with environmental goods treated as conventional outputs. A common approach to evaluate the opportunity cost of providing an environmental good is the exploitation of the distance function's dual relationship to the value function. This implies that the opportunity cost is assumed to be non‐negative. This approach also requires a convex technology set. Focusing on crop diversification for a balanced sample of 44 cereal farms in the East of England for the years 2007–2013, this paper develops a novel opportunity cost measure that does not depend on these strong assumptions. We find that the opportunity cost of crop diversification is negative for most farms.  相似文献   
76.
Using the lenses of institutional theory, this study examines several Entrepreneurial Factor Conditions (National Experts Survey database) while focusing on potential differences of several institutional dimensions between factor- (or production) and innovation-driven countries. This study therefore examines first the extent to which several Scott’s institutional variables (normative, regulative, and cultural-cognitive) differ according to the economic structure of countries participating in NES-GEM. Results indicate that the relevance of both regulative and cultural-cognitive dimensions differ between the group of countries driven by factor (or production) versus innovation, with a single exception, the normative dimension. Second, the study fine tunes the analysis and examines the extent to which the relevance of the aforementioned dimensions differs in two distinct institutional contexts (Portugal and Angola). Results show that the relevance of all institutional variables is different except one, the basic education and training. A possible explanation for these results may be associated to the lack of and fragility of several institutions and the absence of norms and regulations needed for a well-functioning economy, particularly in what concerns the factor (or production)-driven countries. In terms of originality, the study addresses an area of the GEM model that is under-researched.  相似文献   
77.
International traders frequently use forward exchange transactions to hedge their cash flows in foreign currencies. A key issue is whether the forward rates are efficiently priced. There is evidence of time-varying risk premia in forward exchange rates. Are these risk premia systematic or unsystematic? This article uses a market model to explain risk, implying that the risk premium in the forward rate varies pari passu with the beta of the return to speculative forward positions. Assuming the unobserved risk premium is proportional to the forward premium allows testing the predicted relations; the data reject the joint hypotheses of the model and systematic risk. In terms of a simple factor model explaining the covariation of the forward premium, the risk premium, and the expected percentage rate of change of the spot exchange rate, the assumption that the forward premium and the risk premium are proportional can be relaxed without changing the empirical results.  相似文献   
78.
In this article we use an autoregressive fractionally integrated moving average approach to measure the degree of fractional integration of aggregate world CO2 emissions and its five components – coal, oil, gas, cement, and gas flaring. We find that all variables are stationary and mean reverting, but exhibit long-term memory. Our results suggest that both coal and oil combustion emissions have the weakest degree of long-range dependence, while emissions from gas and gas flaring have the strongest. With evidence of long memory, we conclude that transitory policy shocks are likely to have long-lasting effects, but not permanent effects. Accordingly, permanent effects on CO2 emissions require a more permanent policy stance. In this context, if one were to rely only on testing for stationarity and non-stationarity, one would likely conclude in favour of non-stationarity, and therefore that even transitory policy shocks have permanent effects. Our fractional-integration analysis highlights that this is not the case.  相似文献   
79.
To better understand the share of the nonobserved economy (NOE) in the European Union, especially on the PIIGS, we estimate, through the multiple indicators multiple causes model, the path between 1980 and 2013. The model includes (i) the tax burden (disaggregated into direct and indirect taxes), a proxy of regulation burden, the unemployment rate and self-employment as causes of the NOE economy; (ii) the GDP and the labour force participation ratio as indicators of the NOE economy. In particular, the estimated weight of NOE as a percentage of official GDP was always higher in the PIIGS group.  相似文献   
80.
Hyperbolic measures of efficiency and productivity change with respect to a graph representation of production technology allow researchers to consider output and input dimensions simultaneously in measuring producer performance. Hyperbolic efficiency measures have been proposed, but empirical implementation has not followed, either in efficiency analysis or in productivity analysis. The objectives of this paper are to define hyperbolic performance measures on a graph representation of production technology, to motivate their use by stating some of their advantages over their radial counterparts, and to introduce a direct formulation to calculate them making use of Data Envelopment Analysis techniques. The ideas are illustrated by calculating hyperbolic efficiency and Malmquist productivity indexes for a US agricultural panel data set.  相似文献   
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