全文获取类型
收费全文 | 6871篇 |
免费 | 147篇 |
专业分类
财政金融 | 1322篇 |
工业经济 | 612篇 |
计划管理 | 1156篇 |
经济学 | 1451篇 |
综合类 | 72篇 |
运输经济 | 37篇 |
旅游经济 | 103篇 |
贸易经济 | 1136篇 |
农业经济 | 357篇 |
经济概况 | 768篇 |
信息产业经济 | 1篇 |
邮电经济 | 3篇 |
出版年
2021年 | 48篇 |
2020年 | 83篇 |
2019年 | 117篇 |
2018年 | 149篇 |
2017年 | 142篇 |
2016年 | 158篇 |
2015年 | 81篇 |
2014年 | 155篇 |
2013年 | 679篇 |
2012年 | 208篇 |
2011年 | 246篇 |
2010年 | 191篇 |
2009年 | 229篇 |
2008年 | 190篇 |
2007年 | 185篇 |
2006年 | 157篇 |
2005年 | 172篇 |
2004年 | 143篇 |
2003年 | 148篇 |
2002年 | 130篇 |
2001年 | 160篇 |
2000年 | 155篇 |
1999年 | 140篇 |
1998年 | 126篇 |
1997年 | 116篇 |
1996年 | 117篇 |
1995年 | 112篇 |
1994年 | 97篇 |
1993年 | 113篇 |
1992年 | 118篇 |
1991年 | 101篇 |
1990年 | 105篇 |
1989年 | 101篇 |
1988年 | 110篇 |
1987年 | 89篇 |
1986年 | 106篇 |
1985年 | 114篇 |
1984年 | 109篇 |
1983年 | 102篇 |
1982年 | 108篇 |
1981年 | 102篇 |
1980年 | 106篇 |
1979年 | 81篇 |
1978年 | 102篇 |
1977年 | 73篇 |
1976年 | 71篇 |
1975年 | 56篇 |
1974年 | 50篇 |
1973年 | 50篇 |
1972年 | 42篇 |
排序方式: 共有7018条查询结果,搜索用时 0 毫秒
81.
This study quantified technical efficiency and the determinants of observed technical inefficiency of sawmills in Nigeria. A two-stage sampling technique was used to select 170 sawmillers in Ondo and Osun states, while questionnaire was used to obtain data from them between October and December 2003. The stochastic frontier approach was used to estimate technical efficiency of both small- and medium-scale sawmills, while the ordinary least square (OLS) regression analysis was used to estimate the determinants of the observed technical inefficiency. Empirical results indicate that medium-scale sawmillers are more efficient than their small-scale counterparts. However, both groups of sawmillers in Nigeria have potentials to expand their output. 相似文献
82.
83.
84.
85.
The underidentification of linear models with measurement error does not necessarily extend to panel data models, as has been shown by GAiliches and Hausman (1986). We discuss and extend some of their results for a simple case and address particular issues concerning identification and asymptotic variances. 相似文献
86.
87.
88.
Performance lies arise both from individual and from situational causes, but in this article, the attention is on situational causes. These are generally triggered by loyalty to the coalition, which is expressed through the continued use of performance lies. Because performance lies help create a boundary around the coalition that insulates its activities from top management, performance lies enable members of the coalition to exercise a greater degree of internal control. Naturally, such lies are dysfunctional, resulting in the avoidance of difficult issues and problems and compromising the organization's ability to adapt to a changing environment based on accurate information. 相似文献
89.
A formal model of the development process is constructed in order to arrive at a better understanding of the land development process, the change in land prices over time, and the effects of public policy on these variables. The relationship between the rate of interest and the rate of price appreciation on land is shown to depend upon development costs, agricultural opportunity costs, market structure, and the level of Ricardian rents on land. The effects of a land tax and a capital gains tax on the rate of development are also analyzed. 相似文献
90.
Deborah C. Brown Thomas F. Curry Stephen C. Hoyle John H. Seader John J. Tomick Stephen T. Dziuban 《Socio》1992,26(4):241-255
Counternarcotics interdiction efforts have traditionally relied on historically determined sorting criteria or “best guess” to find and classify suspected smuggling traffic. We present a more quantitative approach which incorporates customized database applications, graphics software and statistical modeling techniques to develop forecasting and classification models. Preliminary results show that statistical methodology can improve interdiction rates and reduce forecast error. The idea of predictive modeling is thus gaining support in the counterdrug community. The problem is divided into sea, air and land forecasting, only part of which will be addressed here. The maritime problem is solved using multiple regression in lieu of multivariate time series. This model predicts illegal boat counts by behavior and geographic region. We developed support software to present the forecasts and to automate the process of performing periodic model updates. During the period, the model was in use at. Coast Guard Headquarters. Because of deterrence provided by improved intervention, the vessel seizure rate declined from 1 every 36 hours to 1 every 6 months. Due in part to the success of the sea model, the maritime movement of marijuana has ceased to be a major threat. The air problem is more complex, and required us to locally design data collection and display software. Intelligence analysts are using a customized relational database application with a map overlay to perform visual pattern recognition of smuggling routes. We are solving the modeling portion of the air problem using multiple regression for regional forecasts of traffic density, and discriminant analysis to develop tactical models that classify “good guys” and “bad guys”. The air models are still under development, but we discuss some modeling considerations and preliminary results. The land problem is even more difficult, and data collection is still in progress. 相似文献