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101.
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   
102.
The Brazilian cities as well as many of the large urban centers in the world continue to expand, increasing the demand for mobility and transport, while, at the same time, the same cities are investing in greenhouse gas (GHG) mitigation to avoid climate change. Brazil's urbanization rate increased from 26% in 1940 to almost 70% in 1980. During this period, the Brazilian population tripled and the urban population multiplied by seven. In 2010, the transport sector in São Paulo accounted for 71% of the total emissions released by the energy sector. Ethanol has been considered a fuel with less greenhouse gas emissions, when compared with fossil fuels. However, ethanol production would have to double to meet the expected demand. Electric vehicles (EVs) market is expanding around the world, and is also an option to reduce the transport emissions, if powered by clean electricity. To assess whether the adoption of EVs might bring more benefits than the current ethanol, we develop prospective scenarios supported by the Long-range Energy Alternatives Planning (LEAP) simulation tool, taking a bottom-up tank-to-wheel approach to consider the CO2 emissions of car in São Paulo. The scenario considering a substitution of 25% of gasoline-powered cars by EV in 2030 showed a reduction in energy consumption and CO2 emissions, around 15% and 26% respectively in that year in comparison with 2015. We discuss the interplay between ethanol and EV, also considering emission coefficients from life cycle analysis conducted in Brazil, and concluded EV will have higher positive impact on climate change mitigation than ethanol.  相似文献   
103.
Regional corruptness in China has a positive effect on the profitability of private firms, but not that of state-owned firms. A natural experiment of exogenous trade policy change suggests that corruption may help private firms circumvent government regulation.  相似文献   
104.
江西省耕地后备资源潜力分布及开发组合序列分析   总被引:1,自引:0,他引:1  
[目的]根据耕地后备资源的分布特征研究其开发组合序列是有效开发利用耕地后备资源、补充耕地的重要前提。文章利用江西省耕地后备资源调查评价成果,以县为分级单元对全省耕地后备资源进行开发潜力分级,对江西省耕地后备资源开发组合序列进行研究,从而为江西省耕地后备资源的开发顺序提供参考。[方法]利用Arc GIS空间图形分析法、DPS数据处理系统两维图论聚类等方法确定开发潜力等级以及开发序列。[结果]江西省耕地后备资源开发潜力从高到底依次分为Ⅰ级潜力区、Ⅱ级潜力区、Ⅲ级潜力区和Ⅳ级潜力区,面积分别为2.726 672万hm~2、2.306 897万hm~2、2.873 594万hm~2、1.378 88万hm~2。[结论]根据两维图论聚类法分析结果得知,江西省各县地域相似程度较高可优先开发的组合有进贤县-南昌县-余干县-鄱阳县-彭泽县;袁州区-分宜县-上高县-渝水区-樟树市;进贤县-南昌县-余干县-鄱阳县-都昌县和樟树市-渝水区-上高县-高安市-奉新县-安义县-永修县等。  相似文献   
105.
Generating massive investment for growth and development has been one of the main policy goals of most economies around the globe. Countries, most especially developing ones, are highly susceptible to investment volatility owing largely to the fragile nature of their economies as well as weaknesses in terms of dysfunctional institutions. Therefore, sound economic management suggests the need to better understand possible sources for mitigating the adverse effects of investment volatility. Remittances have been identified as important capital flows which do a good job of dousing macroeconomic volatilities. It is on this basis that the study sought to uncover the causal relationship between remittances and investment volatility via the intermediating role of institutions. Using a panel of 70 countries and the system Generalized Method of Moments (GMM) estimator, three insightful outcomes come to the fore. First, remittances played countercyclical roles across the estimated regressions. Second, institutional quality had no significant role in mitigating investment volatility and lastly, the interactive terms of both remittances and institutions significantly mitigated the negative impacts of investment volatility with the exception of the political component of the institutional architecture. Policy suggestions are drawn based on our results.  相似文献   
106.
Recent non-parametric statistical analysis of high-frequency VIX data (Todorov and Tauchen, 2011) reveals that VIX dynamics is a pure jump semimartingale with infinite jump activity and infinite variation. To our best knowledge, existing models in the literature for pricing and hedging VIX derivatives do not have these features. This paper fills this gap by developing a novel class of parsimonious pure jump models with such features for VIX based on the additive time change technique proposed in Li et al., 2016a, Li et al., 2016b. We time change the 3/2 diffusion by a class of additive subordinators with infinite activity, yielding pure jump Markov semimartingales with infinite activity and infinite variation. These processes have time and state dependent jumps that are mean reverting and are able to capture stylized features of VIX. Our models take the initial term structure of VIX futures as input and are analytically tractable for pricing VIX futures and European options via eigenfunction expansions. Through calibration exercises, we show that our model is able to achieve excellent fit for the VIX implied volatility surface which typically exhibits very steep skews. Comparison to two other models in terms of calibration reveals that our model performs better both in-sample and out-of-sample. We explain the ability of our model to fit the volatility surface by evaluating the matching of moments implied from market VIX option prices. To hedge VIX options, we develop a dynamic strategy which minimizes instantaneous jump risk at each rebalancing time while controlling transaction cost. Its effectiveness is demonstrated through a simulation study on hedging Bermudan style VIX options.  相似文献   
107.
The financial and economic crisis of 2008 and 2009 took a heavy toll on the South African economy. The economy contracted for the first time since 1998 and entered recession during the fourth quarter of 2008. The gross domestic product contraction was soon transmitted to the labour market. Between the second quarters of 2008 and 2009, employment fell by 3.8%. However, not all individuals were hit with the same intensity. Using panel data from a quarterly labour force survey unique in the African context, we find that human capital (i.e. education as years of schooling and workforce experience) provided a buffer against the shock. After controlling for observable characteristics, education and experience showed the potential to entirely offset the effect of the recession on the likelihood of employment. This has important policy implications, as it strengthens the case for strategic investments in human capital and helps identify the unskilled as having the greatest need for social safety net interventions during a recession.  相似文献   
108.
We construct a DSGE search model with endogenous job destruction, incorporating wage rigidities, firing costs and unemployment benefit. We investigate the most important factors in matching the model’s cyclical properties with empirical data, particularly those of job creation rates (JCR) and job destruction rates (JDR). Firing costs assist significantly in explaining the procyclicality of JCR, the negative correlation of JCR and JDR, and the persistence of vacancies. They also decrease the counter-cyclicality of job turnover. We also postulate that the Hosios condition helps explain the negative correlation of JCR and JDR and vacancies’ persistence. Varying wage rigidities and unemployment income, however, do not improve the results.  相似文献   
109.
The zero bound on interest rates introduces a new dimension to the trilemma in international policy. The openness of the international financial market might render monetary policy ineffective, even within a system of fully flexible exchange rates, because shocks that lead to a liquidity trap in one country are propagated through financial markets to other countries. However, the effectiveness of monetary policy can be restored by the imposition of capital controls. We derive the optimal response of monetary policy to a global liquidity trap in the presence of capital controls. We show that, even though capital controls might facilitate effective monetary policy, capital controls are not generally desirable in terms of welfare.  相似文献   
110.
This research shows for the first time that the level of education has a causal, negative effect on the minimum wage. I use 2SLS, with historical educational data as an instrument for the level of education in 2010, and I find that across the US states a one percentage point greater proportion of college graduates is associated with a real minimum wage that is lower by 1.5%–1.6%. Also, in order to control for state-level omitted variables, I regress the change in the minimum wage on the change in education and I find again a negative, and significantly at the 1% level, effect. Minimum wage is a policy that is chosen by governments according to voters’ preferences. The results of this research imply that when the level of education increases voters prefer a lower minimum wage.  相似文献   
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