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   2727篇
  免费   151篇
  国内免费   31篇
财政金融   278篇
工业经济   140篇
计划管理   885篇
经济学   545篇
综合类   253篇
运输经济   30篇
旅游经济   69篇
贸易经济   378篇
农业经济   119篇
经济概况   212篇
  2024年   5篇
  2023年   53篇
  2022年   39篇
  2021年   78篇
  2020年   99篇
  2019年   89篇
  2018年   75篇
  2017年   78篇
  2016年   95篇
  2015年   104篇
  2014年   197篇
  2013年   274篇
  2012年   172篇
  2011年   258篇
  2010年   168篇
  2009年   177篇
  2008年   178篇
  2007年   155篇
  2006年   160篇
  2005年   102篇
  2004年   81篇
  2003年   64篇
  2002年   54篇
  2001年   33篇
  2000年   30篇
  1999年   26篇
  1998年   9篇
  1997年   12篇
  1996年   10篇
  1995年   3篇
  1994年   7篇
  1993年   5篇
  1992年   3篇
  1991年   4篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1985年   3篇
  1984年   1篇
  1983年   3篇
  1979年   1篇
排序方式: 共有2909条查询结果,搜索用时 15 毫秒
91.
We develop an iterative and efficient information-theoretic estimator for forecasting interval-valued data, and use our estimator to forecast the SP500 returns up to five days ahead using moving windows. Our forecasts are based on 13 years of data. We show that our estimator is superior to its competitors under all of the common criteria that are used to evaluate forecasts of interval data. Our approach differs from other methods that are used to forecast interval data in two major ways. First, rather than applying the more traditional methods that use only certain moments of the intervals in the estimation process, our estimator uses the complete sample information. Second, our method simultaneously selects the model (or models) and infers the model’s parameters. It is an iterative approach that imposes minimal structure and statistical assumptions.  相似文献   
92.
The goal of public enterprises is to increase the wealth and happiness of individuals. This target lets them make the investment to fulfill these expectations. However, not all citizens in a country might have the same opportunities. This case requires comparing citizens who live in cities with regard to satisfaction levels. This study consists of two stages. In the first stage, a composite index called the General Satisfaction Index (GSI), which aims to explain the satisfaction levels of citizens living in cities, is obtained by using the Benefit of the Doubt method. Contrary to the previous studies, the satisfaction indicators based on the emotions and senses of citizens are used to construct a composite index. Satisfaction indicators’ contribution to GSI is ensured using the minimum weights. In the second stage of this study, socioeconomic determinants of GSI are investigated in both countrywide and regions by using regularized regression methods. In the result of the regression analyze, it is confirmed that there are different socioeconomic determinants of satisfaction levels for countrywide and each region. For this reason, it is proposed that policymakers should follow different politicizes in each region to increase the satisfaction levels of citizens in the country.  相似文献   
93.
We exploit a regression discontinuity design to provide causal evidence of the relative age effect (RAE) on a long-run adult age outcome: Political selection. We find strong evidence of the RAE in politics in Finland. However, the effect is heterogeneous: We find that male candidates born early in the calendar year have a significantly higher probability of getting elected to the parliament but no similar RAE applies to female candidates nor to municipal elections. Moreover, this effect only takes place in the most competitive parliamentary districts and is present only for some parties. We also find that in all the groups where the RAE does not exist, early-born candidates are under-represented suggesting attrition of talent in the candidate placement. Overall, our results show that seemingly artificial cutoffs imposed by the government have persistent consequences even on the selection to the highest positions of power within a society.  相似文献   
94.
We propose new models for analyzing pairwise comparison data, such as that relating to sports. We focus on changes in players’ strengths and the prediction of future results. Our models are based on the Thurstone-Mosteller and Bradley–Terry models, and make use of the time variation in the parameters. Furthermore, we apply our models to data from the Japanese traditional sport sumo, and analyze this data. The proposed models perform better than the standard Thurstone-Mosteller and Bradley–Terry models according to both the Akaike information criterion and the Brier score. We compare the proposed models in detail by focusing on individual sumo wrestlers.  相似文献   
95.
This paper analyzes platform selection (affiliation) by game developers in the Japanese home video game industry. We develop an elementary model of affiliation by software developers and propose the hypothesis that wider availability of game titles for a platform positively inclines game developers to affiliate with that platform when releasing new game titles. Then, using data for Japan, we estimate a multinomial logit model that includes both the attributes of game developers and the characteristics of platforms, and find evidence supporting this hypothesis. Overall, the findings suggest that game developers expect the indirect network effect to apply, and the prospect of future growth matters to them when deciding with which platform to affiliate.  相似文献   
96.
Theory predicts that market‐timing activities bias Jensen's alpha (JA). However, empirical studies have failed to find consistent evidence of this bias. We tackle this puzzle in a nested model analysis and show that the bias contains an exogenous market component that is unrelated to market‐timing skill. In a comprehensive empirical analysis of US mutual funds, we find that the timing‐induced bias in JA is mainly driven by this market component, which is uncorrelated with measured timing activities. Measures of total performance that allow for timing activities are virtually identical to JA, even if timing activities are present in the evaluated fund. Hence, we conclude that JA is a sufficient measure of total performance.  相似文献   
97.
In this paper, we are proposing a multi-objective mathematical model for the selection of a newly constructed hub and spoke system. The objectives of this model are maximizing aircraft utilization and revenue whilst reducing the commercially infeasible network detour factor. The sensitivity analysis of the model is tackled using weights related to the objectives as well as the network detour factor. The number of available aircraft and the range that an aircraft can reach are also considered in this model. Since Istanbul has already got a hub and spoke system with busy airports on both sides of the city, the model is applied to three other major cities of Turkey, Ankara, Antalya, and Izmir. The test data consists of over 90 cities in Europe and in the Middle East. The data includes unit passenger revenues and operating costs for the segments, distances between cities and hubs, expected load factors and flying times of segments. The scenarios are tested under specific expectations of airline network experts and the results are visualized by using Pareto front graphs. Compared to other candidates, Antalya stands out as a good choice for a new hub and spoke system in Turkey. The results of this model could be helpful for airlines and other airports in Turkey in order to identify their potential and competitive position in relation to their counterparts.  相似文献   
98.
李东明 《价值工程》2015,(15):189-190
本文依据A320货舱门工作原理,结合航线的实际工作经验,总结分析了货舱门无法正常开关的故障原因。从液压油路,电路图两个方面分析了货舱门的操作原理,目的是快速找出最可能故障件,减少航班延误,保障航班安全。  相似文献   
99.
徐岚清 《价值工程》2015,(10):27-28
为了解决在B2C交易实现过程中,由于物流配送供应商的选择不当,而出现配送周期长、费用高、退货退款率增加等问题,本文利用因子分析法探索选择物流配送供应商的合理方法,运用便捷有效的方法帮助电商选择适合自己的物流配送供应商。  相似文献   
100.
Global games emerged as an approach to equilibrium selection. For a general setting with supermodular payoffs, unique selection of equilibrium has been obtained through iterative elimination of strictly dominated strategies. For the case of global games with strategic substitutes, uniqueness of equilibrium has not been proved by iterative elimination of strictly dominated strategies, making the equilibrium less appealing. In this work we provide a condition for dominance solvability in a simple three-player binary-action global game with strategic substitutes. This opens an unexplored research agenda on the study of global games with strategic substitutes.  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