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991.
基于能力异质性的产学研合作创新对象选择   总被引:1,自引:0,他引:1  
顾兴燕  银路 《技术经济》2010,29(11):24-29
通过文献研究,本文发现,企业方和学研方具有不同的能力系统,即双方拥有的能力是异质性的,而这种异质性正是产学研合作创新的基础。双方通过合作不仅可实现优势能力的共享,而且还能有效够弥补对方的能力缺陷,因而产学研合作创新能够实现技术的快速研发和商业化。最后,从产学研合作过程中所需的能力出发,建立了产学研合作创新对象选择的能力耦合图,藉此提高产学研合作的成功率以及合作效率。  相似文献   
992.
Heterogeneous responses of firms to trade protection   总被引:1,自引:0,他引:1  
This paper estimates the effect of antidumping protection on the productivity of domestic import-competing firms. Two key results emerge. First, the productivity of the average firm receiving protection moderately improves, but this is never sufficient to close the productivity gap with firms never involved in antidumping cases. Second, allowing for firm heterogeneity reveals that domestic firms with relatively low initial productivity - laggard firms - have productivity gains during protection, while firms with high initial productivity - frontier firms - experience productivity losses during protection. These results are consistent with recent theories showing that trade policy affects firms differently depending on their initial productivity.  相似文献   
993.
This paper examines the extent to which production location decisions of Taiwanese multinationals reflect underlying patterns of firm productivity. In our theoretical model, heterogeneous firms in a middle-income country decide on the optimal production locations for serving three geographically separate markets: domestic, foreign high-income and foreign low-income. The model shows that the equilibrium decision of a firm depends on the fixed investment costs of establishing foreign subsidiaries, production costs, transportation costs, market size and its own productivity level.

Using firm-level data in 2000, Taiwanese electronics firms are divided into four different categories: non-FDI, investors in China only, investors in the U.S. only, investors in both China and the U.S. We use a multinomial logit model to link firms' location choices with their productivity, controlling for country, industry and other firm characteristics. Our empirical results are consistent with the predictions of the theoretical model. We show that more productive firms engage in outward FDI, with the most productive ones investing in both China and the U.S. We also provide evidence indicating that Taiwanese multinationals investing only in the U.S. are more productive than those investing exclusively in China due to smaller fixed investment costs in China relative to the U.S.  相似文献   

994.
This study investigates the factors behind the recent surge in Japanese imports. It finds evidence of a rise in the long-run income elasticity of total real imports in the mid-1980s. The increase derives from similar behavioral changes at the end-use level and, to a lesser extent, major compositional shifts in the structure of Japanese imports. The behavioral changes in aggregate and end-use imports are likely to reflect important structural developments in the Japanese import market and have potentially significant implications for the impact of macroeconomic policies in Japan on future import performance.  相似文献   
995.
We calculate optimal portfolio choices for a long-horizon, risk-averse investor who diversifies among European stocks, bonds, real estate, and cash, when excess asset returns are predictable. Simulations are performed for scenarios involving different risk aversion levels, horizons, and statistical models capturing predictability in risk premia. Importantly, under one of the scenarios, the investor takes into account the parameter uncertainty implied by the use of estimated coefficients to characterize predictability. We find that real estate ought to play a significant role in optimal portfolio choices, with weights between 12 and 44%. Under plausible assumptions, the welfare costs of either ignoring predictability or restricting portfolio choices to traditional financial assets only are found to be in the order of 150–300 basis points per year. These results are robust to changes in the benchmarks and in the statistical framework.   相似文献   
996.
示踪剂验证井间储层非均质性的现场应用   总被引:1,自引:0,他引:1  
在古城油田B125区V2-5层系进行表面活性剂驱先导试验,注入示踪剂的目的是为了进一步了解注采井间的连通状况、平面水流方向和速度、以及油层非均质性状况。讨论了硫氰酸钠、溴化钠、磷酸二氢钠3种示踪剂在B125区的现场应用情况。在3口注水井中分别注入不同的示踪剂,在对应油井中进行示踪剂检测,根据示踪剂的检出浓度对油藏分层特性进行分析,为调剖和下一阶段注表面活性剂段塞提供了依据。  相似文献   
997.
运用标准差法、FAMA-FRENCH三因子模型法和动态因子Copula模型法等,对2015—2021年中国银行业和房地产业市场各14家主要公司股票收益率进行分析,比较两市场总体风险、系统性风险、异质性风险和市场联合违约概率,并对风险传导方向和效率进行量化检验。结果显示:两市场风险走势基本一致,房地产市场波动比银行市场更剧烈、频繁,房地产业平均系统性风险和平均异质性风险均高于银行业;两市场联合违约概率与风险走势密切相关,系统性风险和异质性风险共同作用提升了市场联合违约概率;风险在两市场间存在交叉传导、反复传导、长期传导的特征,银行业对市场稳定的影响比房地产业更大。因此认为针对银行业市场,须重点关注其可能向其他市场传导的系统性风险,从源头上提高金融系统稳定程度;针对房地产市场,既要从宏观角度把握金融市场风险,也要从微观角度警惕异质性风险。  相似文献   
998.
Wage inequality is on the rise in most developed economies, and this phenomenon has fostered a growing body of research on its potential drivers. Using German data over the period 1985–2009, Card et al. (The Quarterly Journal of Economics 2013, 128(3), 967-1015) argue that rising workplace heterogeneity has contributed substantially to the rise in wage inequality. I revisit their findings in two ways. First, because the generalization of their findings remains an open question, I apply their methodological approach to Danish register data and test whether rising workplace heterogeneity explains a significant share of the rise in wage inequality in Denmark. I find that, contrary to Germany, workplace heterogeneity remained practically stable over time, and this pattern contributed slightly negatively to the rise in wage inequality. Second, I complement Card et al.'s (2013) methods with the variance decomposition exercise proposed by Song et al. (2019) to identify more precisely the sources of the rise in wage inequality in Denmark. Although the rise in wage inequality is partly a between-establishment phenomenon, I show that the strengthening of assortative matching patterns and the rising heterogeneity of workers within establishments are the main drivers of growing inequality.  相似文献   
999.
[目的]文章基于农业技术培训主体异质性的视角,对农户绿色生产技术采纳行为的影响差异性进行理论探讨,并利用四川省836份农户微观调查数据进行检验。[方法]运用Oprobit模型进行实证分析,利用工具变量法(IV-Oprobit)进行内生性处理与稳健性检验。[结果](1)农技培训在1%的水平上显著正向影响农户绿色生产技术采纳行为,培训每增加1次,其采纳有机肥施用等5种绿色生产技术的概率提升3.1%;(2)不同培训主体对农户绿色生产技术采纳的影响具有差异化,以农民合作社为代表的经营性主体培训对农户技术采纳的促进效果最明显,政府农技部门公益性主体培训整体效果优于农业高校和科研院所等准公益性主体;(3)上述影响在不同年龄、受教育程度、家庭社会网络及种植规模的农户群体中也存在明显异质性。[结论] 3类主体开展培训均对绿色生产技术采纳行为有显著影响,农民合作社等经营性主体培训效果最明显。据此,提出构建多元化农业推广培训体系、鼓励农民合作社等经营性主体开展农技培训、推动高校和科研院所的人才科技优势与农技推广培训体系紧密结合等政策建议。  相似文献   
1000.
Intensification of agriculture and industry in salinized areas poses a risk of secondary salinization. Thus, comprehensive and spatially explicit assessments are needed to assist government in developing ecologically sound policies. Few assessments have comprehensively quantified the impacts of multiple anthropogenic activities on salinization as environmental interferences and salinity autocorrelation are largely neglected. This study tried to perform such an assessment by identifying the nature of human impacts on salinization from three aspects in the Yellow River Delta (YRD) of China. A versatile GIS-based spatial autoregression (SAR) was applied to nine selected explainable variables in six sub-region models. Sub-region model was verified as an effective tool of normalizing environmental interferences because more useful spatial information was provided compared to the whole region model. GIS-SAR model fit better and performed better in quantifying human activities, compared to the conventional ordinary least square regression (OLSR) model, as SAR can deal with spatial autocorrelation in soil salinity. Among the well-defined key determinants, oil exploitation and saline aquaculture were aggregative to salinization but only in originally highly saline sub-regions, such as coastal zone and Gleyic Solonchaks (coastal saline moisture soil) area. Two agricultural activities, crop plantation and fertilization, were mainly ameliorators in most sub-regions. The most effective salinization alleviation occurred in moderately saline sub-regions, such as floodplain and Salic Fluvisols (saline moisture soil) area, which benefitted from the development of agroforests and farm ponds. The SAR sub-region model is spatially explicit for spotting the hazardous areas and some suggestions were also provided for the policy makers.  相似文献   
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