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   49891篇
  免费   966篇
  国内免费   1篇
财政金融   9333篇
工业经济   3636篇
计划管理   7975篇
经济学   11114篇
综合类   625篇
运输经济   337篇
旅游经济   848篇
贸易经济   7688篇
农业经济   2412篇
经济概况   6764篇
信息产业经济   1篇
邮电经济   125篇
  2021年   288篇
  2020年   492篇
  2019年   739篇
  2018年   981篇
  2017年   975篇
  2016年   970篇
  2015年   631篇
  2014年   1049篇
  2013年   4933篇
  2012年   1410篇
  2011年   1559篇
  2010年   1277篇
  2009年   1475篇
  2008年   1490篇
  2007年   1318篇
  2006年   1203篇
  2005年   1092篇
  2004年   1104篇
  2003年   1036篇
  2002年   1049篇
  2001年   985篇
  2000年   974篇
  1999年   892篇
  1998年   872篇
  1997年   871篇
  1996年   864篇
  1995年   754篇
  1994年   794篇
  1993年   839篇
  1992年   816篇
  1991年   828篇
  1990年   732篇
  1989年   634篇
  1988年   629篇
  1987年   626篇
  1986年   649篇
  1985年   959篇
  1984年   905篇
  1983年   873篇
  1982年   815篇
  1981年   730篇
  1980年   775篇
  1979年   719篇
  1978年   604篇
  1977年   561篇
  1976年   437篇
  1975年   464篇
  1974年   412篇
  1973年   386篇
  1972年   292篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
When forecasting decisions in conflict situations, experts are often advised to figuratively stand in the other person’s shoes. We refer to this as “role thinking”, because, in practice, the advice is to think about how other protagonists will view the situation in order to predict their decisions. We tested the effect of role thinking on forecast accuracy. We obtained 101 role-thinking forecasts of the decisions that would be made in nine diverse conflicts from 27 Naval postgraduate students (experts) and 107 role-thinking forecasts from 103 second-year organizational behavior students (novices). The accuracy of the novices’ forecasts was 33% and that of the experts’ was 31%; both were little different from chance (guessing), which was 28%. The small improvement in accuracy from role-thinking strengthens the finding from earlier research that it is not sufficient to think hard about a situation in order to predict the decisions which groups of people will make when they are in conflict. Instead, it is useful to ask groups of role players to simulate the situation. When groups of novice participants adopted the roles of protagonists in the aforementioned nine conflicts and interacted with each other, their group decisions predicted the actual decisions with an accuracy of 60%.  相似文献   
912.
913.
This paper describes the second model considered in the computational suite project that compares the performance of different numerical algorithms. It is a multi-country model in which countries face different productivity shocks. Solving such models is a challenging numerical problem unless the number of countries is small. The solutions are functions of a large set of arguments and the functional forms are unknown. Moreover, the solution procedures have to deal with high-dimensional integration problems.  相似文献   
914.
915.
This paper introduces an integrated algorithm for forecasting electricity consumption (EL) based on fuzzy regression, time series and principal component analysis (PCA) in uncertain markets such as Iran. The algorithm is examined by mean absolute percentage error, analysis of variance (ANOVA) and Duncan Multiple Range Test. PCA is used to identify the input variables for the fuzzy regression and time series models. Monthly EL in Iran is used to show the superiority of the algorithm. Moreover, it is shown that the selected fuzzy regression model has better estimated values for total EL than time series. The algorithm provides as good results as intelligent methods. However, it is shown that the algorithm does not require utilization of preprocessing methods but genetic algorithm, artificial neural network and fuzzy inference system require preprocessing which could be a cumbersome task to deal with ambiguous data. The unique features of the proposed algorithm are three fold. First, two type of fuzzy regressions with and without preprocessed data are prescribed by the algorithm in order to minimize the bias. Second, it uses PCA approach instead of trial and error method for selecting the most important input variables. Third, ANOVA is used to statistically compare fuzzy regression and time series with actual data.  相似文献   
916.
917.
Relatively little is understood about factors triggering entrepreneurial behaviour within organizations not driven by profit motives. Governance plays an important role in non‐profits, particularly boards of directors. Integrating resource‐based theory and entrepreneurial orientation research, we examine the influence of non‐profit boards as strategic resources shaping the organization's entrepreneurial orientation and performance. In particular, we focus on the non‐profit board's underlying behavioural orientations, or the extent to which the board is strategic, activist, conservative, and cohesive. Findings from a cross‐sectional survey on arts and culture organizations demonstrate that three of these behavioural orientations impact levels of entrepreneurship occurring within non‐profits. Higher levels of entrepreneurship affect social performance, but not financial performance.  相似文献   
918.
919.
This paper presents an exploratory study to assess the efficiency level of construction companies worldwide, exploring in particular the effect of location and activity in the efficiency levels. This paper also provides insights concerning the convergence in efficiency across regions. The companies are divided in three regions (Europe, Asia and North America), and in the three main construction activities (Buildings, Heavy Civil and Specialty Trade). We analyze a sample of 118 companies worldwide between 1995 and 2003. Data envelopment analysis is used to estimate efficiency, and the Malmquist index is applied for the evaluation of productivity change. Both methods were complemented by bootstrapping to refine the estimates obtained. A panel data truncated regression with categorical regressors is used to explore the impact of location and activity in the efficiency levels. The results reveal that the efficiency of North American companies is higher than the European and Asian counterparts. Other important conclusion points to a convergence in efficiency levels across regions as in North America productivity remains stable, whereas in Asia and Europe productivity improves.  相似文献   
920.
The popular use of graded paired comparisons in empirical studies assessing consumers’ preferences, and the potential effect of cross-national differences in (extreme) response styles on the quality of graded paired comparison data, supply ample reasons for an empirical verification of the cross-national validity of such scales. Using data from a cross-national margarine brand study including fourteen different nations (N = 4,560), we found sufficient statistical evidence for cross-national bias due to existing cross-national differences in extreme responses. However, the low values reported for effect size measures (intra-class correlation coefficient, R 2 value) indicated that the impact of the cross-national bias is marginal. The findings from our study provided empirical support for the hypothesis that graded paired comparison data can be meaningfully compared across nations.  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