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   16781篇
  免费   851篇
  国内免费   208篇
财政金融   1125篇
工业经济   1353篇
计划管理   6928篇
经济学   1691篇
综合类   2178篇
运输经济   127篇
旅游经济   170篇
贸易经济   1729篇
农业经济   1132篇
经济概况   1407篇
  2024年   41篇
  2023年   222篇
  2022年   316篇
  2021年   448篇
  2020年   441篇
  2019年   250篇
  2018年   259篇
  2017年   273篇
  2016年   347篇
  2015年   574篇
  2014年   1437篇
  2013年   1212篇
  2012年   1606篇
  2011年   2089篇
  2010年   1694篇
  2009年   977篇
  2008年   1103篇
  2007年   1033篇
  2006年   881篇
  2005年   706篇
  2004年   498篇
  2003年   370篇
  2002年   260篇
  2001年   198篇
  2000年   158篇
  1999年   117篇
  1998年   62篇
  1997年   54篇
  1996年   45篇
  1995年   26篇
  1994年   23篇
  1993年   27篇
  1992年   21篇
  1991年   23篇
  1990年   11篇
  1989年   9篇
  1988年   4篇
  1987年   2篇
  1986年   4篇
  1985年   6篇
  1984年   3篇
  1983年   4篇
  1982年   3篇
  1981年   2篇
  1980年   1篇
排序方式: 共有10000条查询结果,搜索用时 23 毫秒
101.
研究目的:针对城市化进程中的土地低效利用以及过度集约问题,探讨不同城市化发展阶段的土地集约利用状况及适度集约利用状态。研究方法:采用匹配度模型、曲线估计模型和多目标规划模型,对山西省的土地集约利用进行分区优化。研究结果:(1)1999—2012年山西省土地集约利用与城市化水平之间的匹配趋势逐渐由失调、磨合向协调转变,但不同地区之间的匹配水平差距却在逐渐扩大;(2)2018年山西省城市化水平处于低于30%、30%~70%和高于70%时,以单位城镇建设用地固定资产投资额为表征的土地适度集约利用值分别为249.93万元/km~2、367.57万元/km~2和692.72万元/km~2,两项指标叠加全省可划分为平稳发展区、重点挖潜区和优化拓展区,并提出了不同地区差别化的建设用地管控政策。研究结论:不同城市化发展阶段的土地适度集约利用研究能为制定区域差别化政策提供参考,以促进该地区的土地集约利用水平达到适度状态。  相似文献   
102.
Using an innovative dataset built by merging survey and administrative data, we provide new estimates of intergenerational earnings’ inequality between fathers and sons in Italy, extending previous evidence in several directions. We rely on the TSTSLS method to predict fathers’ earnings and compute intergenerational elasticities and imputed rank–rank slopes, trying to reduce estimation biases. Confirming previous evidence, we find that Italy is characterized by a high intergenerational inequality in cross-country comparison. Extending previous analyses, we show that the intergenerational association increases when sons at older ages and multi-annual averages of pseudo-fathers’ and sons’ earnings are considered. We also find that the intergenerational persistence differs across geographical macro-areas and is high also for daughters, especially when family earnings are considered. Furthermore, estimates where possible mediating factors of the parental influence are included among the covariates show that a high intergenerational association persists when sons’ education and occupation are controlled for.  相似文献   
103.
Data envelopment analysis (DEA) has recently become relatively popular with road safety experts. Therefore, various decision-making units (DMUs), such as EU countries, have been assessed in terms of road safety performance (RSP). However, the DEA has been criticized because it evaluates DMUs based only on the concept of self-assessment, and, therefore does not provide a unique ranking for DMUs. Therefore, cross efficiency method (CEM) was developed to overcome this shortcoming. Peer-evaluations in addition to self-evaluation have made the CEM to be recognized as an effective method for ranking DMUs. The traditional CEM is based only on the standard CCR (Charnes, Cooper and Rhodes) model, and it evaluates DMUs according to their position relative to the best practice frontier while neglecting the worst practice frontier. However, the DMUs can also be assessed based on their position relative to the worst practice frontier. In this regard, the present study aims to provide a double-frontier CEM for assessing RSP by taking into account the best and worst frontiers simultaneously. For this purpose, the cross efficiency and cross anti-efficiency matrices are generated.Even though a weighted average method (WAM) is most frequently used for cross efficiency aggregation, the decision maker's (DM) preference structure may not be reflected. For this reason, the present study mainly focuses on the evidential reasoning approach (ERA), as a nonlinear aggregation method, rather than the linear WAM. Equal weights are often used for cross efficiency aggregation; consequently, the effect of the DM's subjective judgments in obtaining the overall efficiency is ignored. In this respect, the minimax entropy approach (MEA) and the maximum disparity approach (MMDA) are applied for determining the ordered weighted averaging (OWA) operator weights for cross efficiency aggregation. The weighted cross efficiencies and cross anti-efficiencies are then aggregated using the ERA. Finally, the proposed method, called DF-CEM-ERA, is used to evaluate the RSP of EU countries as well as Serbian police departments (PDs).  相似文献   
104.
We consider methods for estimating the means of survey variables in domains of a finite population, where sample sizes are too small to obtain reliable direct estimates. We construct generalized compositions from the direct and traditional design-based synthetic estimators and propose the methodology for evaluating their coefficients. This methodology measures similarities among sample elements and estimates of the domain means. We propose the compositions for two cases of auxiliary information: domain-level characteristics are available; true means of auxiliary variables are available for the estimation domains, and unit-level auxiliary vectors are known for the sample elements. In the simulation study, we show where the generalized compositions improve the traditional synthetic and composite estimators.  相似文献   
105.
Using discretionary accruals to proxy for earnings quality, this study investigates whether and how the first voluntary internal control reporting in 2007 is associated with earnings quality in China. We find that earnings quality is higher in 2007, yet not in 2006, for public companies issuing a first-time voluntary unqualified internal control report, compared with listed firms not issuing an internal control report. Our findings are consistent with a signalling of performance explanation and inconsistent with a signalling of effectiveness explanation. We also find that earnings quality is lower for public companies issuing an internal control report mentioning a weakness, compared with public companies not issuing an internal control report. Overall, our study suggests that public companies conduct diligent self-assessments when issuing a first-time voluntary unqualified internal control report. Consequently, there is an improvement in earnings quality.  相似文献   
106.
Genuine reviews are essential for financial performance and for customer trust. In the case of a negative experience, withholding negative reviews may lead to biased online information. This paper aims to investigate two factors that may prompt customers to withhold their complaints (i.e., identity disclosure and locus of control). The study adopts a sequential exploratory mixed-method approach. An exploratory interview phase compares public vs anonymous online environments, and explores the reasons why dissatisfied customers might decide not to complain. An experiment then shows that vulnerability is a key mechanism preventing negative reviews. This effect is exaggerated when customers perceive that they do not have control over the events happening in their lives (i.e., external locus of control). Our work uncovers an important determinant of online complaint behavior, vulnerability. It also offers practical suggestions, such as improving confidentiality, to increase a customer's willingness to complain following a negative experience.  相似文献   
107.
构建了分析河西走廊物流业效率演化的指标体系,基于2009-2017年河西走廊物流业统计数据,运用DEA-Malmquist指数法测算了各市物流业效率和技术进步率,采用Tobit回归模型分析了该地区物流业效率的影响因素,并从省内、省域间、各经济区域间三个方面进行了对比分析。实证分析表明,相较于全国各省市地区,河西走廊物流业整体水平较低,物流业效率和技术进步率的强正相关性普遍存在,其物流业发展对政策偏向具有较强的依赖性;同时,技术进步率低下和基础设施匮乏也是制约物流业发展的重要因素。基于此,从政策照顾与资金投入、科技进步与管理水平和市场运营与体系建设三个方面,为河西走廊物流业发展提出了建议与改善措施。  相似文献   
108.
选择以农业上市公司敦煌种业为研究对象,以企业2014—2019年的报表数据为基础,采用功效系数法并以国务院国资委所编写的《企业绩效评价标准值》中国有企业绩效评价体系作为参考,构建对农业企业的财务指标评价体系,对敦煌种业2014-2019年企业财务指标的表现进行纵向分析,选择同行业中营业收入水平较高的北大荒进行横向对比,通过对比发现敦煌种业的问题主要体现在盈利能力和资产质量方面,对此提出了改进措施及建议。  相似文献   
109.
本文基于预期功能安全,采用功能分解方法,总结出部分车辆自动紧急制动(AEB)系统失效和误作用场景,并从中选取典型场景作为测试场景,开展不同车型的实车道路试验,总结出AEB系统的缺陷与隐患分类。希望此类研究能为AEB系统失效和误作用测试标准的制定提供参考。  相似文献   
110.
Insourcing to countermand previous outsourcing decisions is becoming a widespread practice among firms. While the underlying performance drivers for firms (e.g., lead times, responsiveness, or security of supply) are well understood, the behavioural aspects underlying managerial decision-making processes regarding insourcing remain overlooked in empirical research. We study the effects of managers' attitudes toward insourcing, their perceived behavioural control (PBC) over the respective insourcing decision, and the effect of mimetic pressure on insourcing decision intentions and behaviour, while grounding our model in the Theory of Planned Behaviour (TPB). We test hypotheses with data gathered in a vignette-based experiment among 145 managers and apply stepwise regression analysis to find support for the positive effects of attitude and mimetic pressure on intentions to insource. Our results found no support for the effect of managers’ PBC. We find moderation effects among the internal drivers (attitude and PBC) and between internal and external drivers (attitude and mimetic pressure) on insourcing behaviour. With these findings, we provide evidence of a unique boundary condition to the TPB in the insourcing context by explaining supply chain design choices with neo-classical and behavioural theory. We emphasize important behavioural aspects in insourcing decision-making and caution supply managers in this regard.  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