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   16767篇
  免费   434篇
  国内免费   1篇
财政金融   3693篇
工业经济   1151篇
计划管理   2863篇
经济学   3755篇
综合类   199篇
运输经济   84篇
旅游经济   270篇
贸易经济   2515篇
农业经济   852篇
经济概况   1740篇
邮电经济   80篇
  2020年   185篇
  2019年   263篇
  2018年   292篇
  2017年   346篇
  2016年   333篇
  2015年   235篇
  2014年   355篇
  2013年   1712篇
  2012年   428篇
  2011年   474篇
  2010年   410篇
  2009年   466篇
  2008年   409篇
  2007年   405篇
  2006年   374篇
  2005年   338篇
  2004年   299篇
  2003年   360篇
  2002年   328篇
  2001年   330篇
  2000年   362篇
  1999年   306篇
  1998年   313篇
  1997年   318篇
  1996年   293篇
  1995年   296篇
  1994年   307篇
  1993年   302篇
  1992年   321篇
  1991年   334篇
  1990年   257篇
  1989年   212篇
  1988年   230篇
  1987年   213篇
  1986年   252篇
  1985年   341篇
  1984年   330篇
  1983年   288篇
  1982年   306篇
  1981年   330篇
  1980年   280篇
  1979年   279篇
  1978年   251篇
  1977年   187篇
  1976年   183篇
  1975年   191篇
  1974年   145篇
  1973年   158篇
  1972年   119篇
  1971年   103篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
We collected 469 frontal face images of Ukrainian cabinet ministers who were in office in 2000–2020. For each image, the minister's body mass index was estimated using a computer vision algorithm. The time series of median estimated body mass index of cabinet ministers co-moves over time with two existing measures of corruption – World Bank worldwide governance indicator Control of Corruption, and the discrepancy between the quantity of luxury wristwatches exported from Switzerland to Ukraine (reported by Swiss statistics) and the corresponding quantity imported by Ukraine from Switzerland (reported by Ukrainian statistics).  相似文献   
2.
We examine asymmetry in the loss functions of South Korean consumers' and the Bank of Korea's (BOK) inflation forecasts, and test the rationality of these forecasts under the assumption of a possible asymmetric loss function. Under an asymmetric loss function, we find evidence of asymmetry and support for rationality. We also examine whether the BOK's forecasts incorporate respective forecasts and consensus forecasts efficiently. They broadly use available information efficiently, and their results are robust to inflation‐targeting measures and the recent global financial crisis. However, our results suggest that the information efficiency of the BOK's forecasts for consumers was affected during the period 2007–2008.  相似文献   
3.
The main objective of this paper it to model the dynamic relationship between global averaged measures of Total Radiative Forcing (RTF) and surface temperature, measured by the Global Temperature Anomaly (GTA), and then use this model to forecast the GTA. The analysis utilizes the Data-Based Mechanistic (DBM) approach to the modelling and forecasting where, in this application, the unobserved component model includes a novel hybrid Box-Jenkins stochastic model in which the relationship between RTF and GTA is based on a continuous time transfer function (differential equation) model. This model then provides the basis for short term, inter-annual to decadal, forecasting of the GTA, using a transfer function form of the Kalman Filter, which produces a good prediction of the ‘pause’ or ‘levelling’ in the temperature rise over the period 2000 to 2011. This derives in part from the effects of a quasi-periodic component that is modelled and forecast by a Dynamic Harmonic Regression (DHR) relationship and is shown to be correlated with the Atlantic Multidecadal Oscillation (AMO) index.  相似文献   
4.
This article examines the role of national culture, measured by conflict avoidance, on the relationship between leader–member exchange (LMX) and individual employee voice. Using data collected from automotive industry employees in the United States and Korea, the findings show that conflict avoidance is negatively related to employee voice and also moderates the relationship between LMX and employee voice in the Korean sample. In particular, the relationship between LMX and voice becomes less positive when conflict avoidance is high. On the other hand, conflict avoidance does not have a direct effect on employee voice as well as an interactive effect with LMX on employee voice in the U.S. sample. This study, therefore, highlights the importance of the national culture in the comparative study of employee voice.  相似文献   
5.
6.
7.
Against the background of supply-side structural reform and the real estate financialisation in China, this study investigates the impact of real estate holdings on R&D investment using data of enterprises listed on the Shanghai and Shenzhen stock exchanges. Our empirical results yield five main findings. First, enterprises holding more real estate assets face more serious financial constraints, thus restraining corporate innovation efficiency. Second, when the profit margin gap between entity enterprises and the real estate industry is larger, enterprises are more inclined to transfer industrial capital into the real estate industry, thus reducing R&D investment. Third, when the degree of marketisation is high, intensified market competition, the optimal allocation of factor and product markets, and stronger patent protection will weaken the restraining effect of corporate real estate holdings on R&D investment. Fourth, monopoly enterprises obtain potential profits more than undertaking risks from the real estate industry, they are more willing to hold real estate, thus strengthening the restraining effect of real estate holdings on innovation. Finally, investors' regional preference intensifies the restraining effect of corporate real estate holdings on R&D investment. Our empirical evidence can guide entity enterprises on how to effectively balance short-term (non-productive) and long-term (productive) capital investment.  相似文献   
8.
This paper studies the expansion of an option price (with bounded Lipschitz payoff) in a stochastic volatility model including a local volatility component. The stochastic volatility is a square root process, which is widely used for modeling the behavior of the variance process (Heston model). The local volatility part is of general form, requiring only appropriate growth and boundedness assumptions. We rigorously establish tight error estimates of our expansions, using Malliavin calculus. The error analysis, which requires a careful treatment because of the lack of weak differentiability of the model, is interesting on its own. Moreover, in the particular case of call–put options, we also provide expansions of the Black–Scholes implied volatility that allow to obtain very simple formulas that are fast to compute compared to the Monte Carlo approach and maintain a very competitive accuracy.  相似文献   
9.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components.  相似文献   
10.
We tested relationships between employee quit rates and two bundles of human resource (HR) practices that reflect the different interests of the two parties involved in the employment relationship. To understand the boundary conditions for these effects, we examined an external contingency proposed to influence the exchange-based effects of HR practices on subsequent quit rates – the local industry-specific unemployment rate – and an internal contingency proposed to shape employees’ conceptualization of their exchange relationship – their employment status (i.e. full-time, part-time and temporary employment). Analyses of lagged data from over 200 Canadian establishments show that inducement HR practices (e.g. extensive benefits) and performance expectation HR practices (e.g. performance-based bonuses) had different effects on quit rates, and the former effect was moderated by unemployment rate. The effects of HR practices on quit rates did not differ between FT and PT employees, but a different pattern of main and interactive effects was found among temporary workers. These findings suggest that employees’ exchange-based decisions to leave may be less affected by the number of hours they expect to work each week, and more by the number of weeks they expect to work.  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