首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   298篇
  免费   4篇
财政金融   60篇
工业经济   1篇
计划管理   108篇
经济学   59篇
综合类   21篇
运输经济   2篇
旅游经济   4篇
贸易经济   24篇
农业经济   12篇
经济概况   11篇
  2023年   1篇
  2022年   6篇
  2021年   2篇
  2020年   3篇
  2019年   8篇
  2018年   8篇
  2017年   12篇
  2016年   9篇
  2015年   9篇
  2014年   13篇
  2013年   22篇
  2012年   23篇
  2011年   25篇
  2010年   17篇
  2009年   25篇
  2008年   29篇
  2007年   21篇
  2006年   12篇
  2005年   11篇
  2004年   7篇
  2003年   6篇
  2002年   4篇
  2001年   12篇
  2000年   2篇
  1999年   2篇
  1998年   1篇
  1997年   2篇
  1996年   3篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1987年   1篇
  1984年   1篇
  1982年   1篇
排序方式: 共有302条查询结果,搜索用时 31 毫秒
1.
The inflation rate is a key economic indicator for which forecasters are constantly seeking to improve the accuracy of predictions, so as to enable better macroeconomic decision making. Presented in this paper is a novel approach which seeks to exploit auxiliary information contained within inflation forecasts for developing a new and improved forecast for inflation by modeling with Multivariate Singular Spectrum Analysis (MSSA). Unlike other forecast combination techniques, the key feature of the proposed approach is its use of forecasts, i.e. data into the future, within the modeling process and extracting auxiliary information for generating a new and improved forecast. We consider real data on consumer price inflation in UK, obtained via the Office for National Statistics. A variety of parametric and nonparametric models are then used to generate univariate forecasts of inflation. Thereafter, the best univariate forecast is considered as auxiliary information within the MSSA model alongside historical data for UK consumer price inflation, and a new multivariate forecast is generated. We find compelling evidence which shows the benefits of the proposed approach at generating more accurate medium to long term inflation forecasts for UK in relation to the competing models. Finally, through the discussion, we also consider Google Trends forecasts for inflation within the proposed framework.  相似文献   
2.
In this paper, we illustrate the real function relationship between the stock returns and change of investor sentiment based on the nonparametric regression model. The empirical results show that when the change of investor sentiment is moderate, the stock return is positively correlated with the change of investor sentiment, presenting an obvious momentum effect. However, the stock return is negatively correlated with the change of investor sentiment if the change of investor sentiment is dramatic, presenting significant reversal effects. Moreover, the degree of reversal effect caused by extremely optimistic sentiment is greater than that driven by extremely pessimistic sentiment, which shows a significant asymmetry. Our findings offer a partial explanation for financial anomalies such as the mean reversion of stock returns, the characteristic of slow rise and steep fall in China's stock market and so on.  相似文献   
3.
食品检测实验室中最为重要的就是质量监督管理工作,做好质量监督有利于提高实验室工作人员的质检与管理能力,进而推动有关人员的学习进步,以胜任工作岗位,提高该食品检测实验室的质量检测水平,确保检测数据的有效性与无误性。但现阶段我国的实验室由于缺乏统一的行业标准,导致其质量监督工作水平参差不齐,出现了一系列不利于质量检测的因素,比如质量监督目的不明、质量监督内容不完整、质量监督措施不完善等不足,都会影响该实验室对于食品的检测。因此,本文主要就食品检测实验室的质量监督方法进行探究,从各个方面指出质量监督的技术要点。  相似文献   
4.
在日益复杂的产品需求和生产环境下,企业面临的生产难题也更加复杂,如何科学系统地使用创新方法解决企业生产难题,是长期困扰企业的问题。研究多个创新方法集成与融合应用概念模型,构建以企业生产难题为导向的多创新方法集成与融合应用理论体系,并基于多创新方法集成与融合应用过程,提出从多个维度指导企业实施多创新方法集成与融合应用的“LCUE矩阵法”。最后,结合某空调装配企业生产实际,以价值流方法为模板,基于LCUE矩阵实施多创新方法集成与融合应用,有效解决了企业生产难题,验证了多创新方法集成与融合应用及LCUE矩阵法的可行性。  相似文献   
5.
This article applies inductive analytic techniques to identify and elaborate on two recurring themes that underpin the core puzzle of entrepreneurship research — where entrepreneurial opportunities come from. The first theme is the unique role of imprinting, or the profound influence of social and historical context in constraining the perceptual apparatus of entrepreneurs and delimiting the range of opportunities for innovation available to them. Second, our analysis offers insight into the counterbalancing role of reflexivity, operating at both individual and collective levels of analysis, in generating the ability of entrepreneurs to overcome the constraints of imprinting. These insights are based on a thematic review of the nine studies that comprise this special issue on qualitative research. The nine studies, individually and each in their own way, offer key insights into how we might better understand the emergence of entrepreneurial opportunity.  相似文献   
6.
针对产品生产和加工方法贸易措施的违法性分析   总被引:1,自引:0,他引:1  
在GATT—WTO体系内部,针对产品生产和加工方法贸易措施的合法性,以及如何规范允许使用的针对产品生产和加工方法贸易措施的讨论甚为激烈,成为最有争议的焦点问题之一。本文根据对WTO协议中的GATT第1条、第3条、第20条,以及《技术性贸易壁垒协议》相关条文和案例的研究,分析了针对产品生产和加工方法贸易措施的违法性及其可能的负面效应,以供进一步的研究参考。  相似文献   
7.
Economic variables usually follow a dynamic trend pattern. However, it is difficult to estimate this trend precisely as numerous economically- and statistically-based estimation methods exist. This contribution proposes a data-driven nonparametric trend that is local polynomial, to improve arbitrary trend estimations of commonly used methods concerning the selection of the smoothing parameter and the dependence structure. An iterative plug-in (IPI) algorithm determines the bandwidth endogenously and allows a theory-based interpretation of the length of growth processes. This length of the bandwidth reflects the lengths of the steady state periods. Consequently, the bandwidth identifies the time period of stable economic conditions and can detect economic changes. To demonstrate the power of this estimation approach, an extensive simulation study is performed. Furthermore, examples using US and UK GDP data along with a guide for the optimal choice of algorithms for empirical applications are provided. This proposed method yields new insights for growth dynamics, cyclical movements and their dependence.  相似文献   
8.
We propose to forecast the Value-at-Risk of bivariate portfolios using copulas which are calibrated on the basis of nonparametric sample estimates of the coefficient of lower tail dependence. We compare our proposed method to a conventional copula-GARCH model where the parameter of a Clayton copula is estimated via Canonical Maximum-Likelihood. The superiority of our proposed model is exemplified by analyzing a data sample of nine different bivariate and one nine-dimensional financial portfolio. A comparison of the out-of-sample forecasting accuracy of both models confirms that our model yields economically significantly better Value-at-Risk forecasts than the competing parametric calibration strategy.  相似文献   
9.
This article analyses adoption of farm‐based irrigation water saving techniques, based on a cross‐sectional data set of 357 farmers in the Guanzhong Plain, China. Approximately 83% of the farmers use at least one farm‐based water‐saving technique. However, the traditional, inefficient techniques border and furrow irrigation are still prevalent whereas the use of advanced, more efficient techniques is still rather rare. We develop and estimate an adoption model consisting of two stages: awareness of water scarcity and intensity of adoption. We find that awareness of water scarcity and financial status enhance adoption of more advanced techniques whereas access to better community‐based irrigation infrastructure discourages it. We furthermore find both community‐based irrigation infrastructure and farm‐based irrigation water‐saving techniques have mitigating effects on production risk. From the results it follows that adoption can be stimulated via financial support and via extension aimed at enhancing awareness of water scarcity.  相似文献   
10.
Though most landscape ecologists have integrated scaling issues in their works, these issues are often disregarded in landscape perception and preference studies. Researchers base their studies on a predefined single scale to assess the landscape, and they pay little attention to the scale specificity of their analysis and recommendations. We reconsidered three landscape assessment studies from our research unit in light of scaling issues. In addition to the scale of the assessed landscape, researchers should address the scale of the landscape surrogate that is submitted for assessment, including the spatial references of the people surveyed and the target level of application of the results. Indeed, many of the landscape assessment methods mix different landscape notions and scales. Therefore, we recommend the cautious use of these assessments, the integration of qualitative insights in addition tithe scoring and paying attention to the perception scale, as defined by Fairclough (2006).  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号