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   12402篇
  免费   216篇
财政金融   2185篇
工业经济   859篇
计划管理   2055篇
经济学   2645篇
综合类   95篇
运输经济   79篇
旅游经济   166篇
贸易经济   1902篇
农业经济   705篇
经济概况   1885篇
信息产业经济   1篇
邮电经济   41篇
  2020年   109篇
  2019年   175篇
  2018年   269篇
  2017年   244篇
  2016年   244篇
  2015年   154篇
  2014年   264篇
  2013年   1063篇
  2012年   351篇
  2011年   349篇
  2010年   290篇
  2009年   349篇
  2008年   338篇
  2007年   292篇
  2006年   280篇
  2005年   242篇
  2004年   245篇
  2003年   239篇
  2002年   248篇
  2001年   219篇
  2000年   250篇
  1999年   219篇
  1998年   205篇
  1997年   185篇
  1996年   202篇
  1995年   181篇
  1994年   193篇
  1993年   190篇
  1992年   208篇
  1991年   205篇
  1990年   206篇
  1989年   178篇
  1988年   143篇
  1987年   151篇
  1986年   169篇
  1985年   247篇
  1984年   224篇
  1983年   194篇
  1982年   199篇
  1981年   199篇
  1980年   188篇
  1979年   188篇
  1978年   166篇
  1977年   153篇
  1976年   148篇
  1975年   150篇
  1974年   116篇
  1973年   114篇
  1972年   106篇
  1971年   83篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
191.
192.
193.
194.
This paper presents a framework for estimating an indirect production function and then applies it to aggregate US agriculture. Issues addressed include tests of standard hypotheses about the underlying technology (homotheticity, neutral technical change, etc.) as well as examination of consistency in aggregation and the effects of changes in the level of aggregate expenditure on farm output. Since there already exist several studies empirically describing agricultural production technologies with indirect objective functions, one might fairly ask whether this paper really breaks any new ground? We feel that it does. One reason is that existing studies (e.g. Binswanger, 1974; Lopez, 1980; Ball and Chambers, 1982; Ray, 1982; and Weaver, 1983) all rely on either profit or cost functions. To date there appears to be only one study using an indirect production (Appelbaum, 1979), and it is not in agriculture. This seems unfortunate because there are many instances in agriculture for which an indirect production function (or revenue function approach) seems more appropriate. The reason why relates directly to one's belief about the objective function and constraints farmers face. Ultimately, it seems plausible in a certainty framework that producers maximize profits. And since cost minimization and output maximization are just constrained versions of profit maximization, both cost and indirect production functions are more appropriately viewed as restricted profit functions. What differs is the constraint. Assuming cost minimization implies that farmers are constrained by a fixed output which they must produce; in most instances, this is implausible. More likely, the level of output is itself a choice variable. Output maximization, on the other hand, suggests that the main constraint is the amount of money that producers can muster to hire resources. In other words, farmers may face binding constraints in obtaining the profit maximizing level on expenditure on input utilization. One might think that expenditure may not be a binding constraint because there exists a relatively active US credit market. However, the US credit market is far from being perfectly competitive in a stylized sense, and thus, the possibility of a farmer being able to finance a given level of expenditure may be limited.

Readers familiar with the dual approach to production problems may already be asking why these ideas rule out cost functions since it is well known that the cost function is the distance function of the indirect production function (Blackorby et al., 1978)? In principle, therefore, one could always estimate a cost function and then invert it to obtain the indirect production function. There are two problems with this approach: the first is that if output maximization is truly the objective, output is not predetermined and cannot be treated as exogenous in cost function estimation. Second, estimation of direct and indirect functions using the same data set does not always yield comparable results. Estimation of a transcendental logarithmic (translog) indirect production function and a translog cost function, separately, does not generally yield identical estimates of the Allen elasticities of substitutions. Solving the first problem in simple, but the second suggests that estimation should proceed on the basis of the objective function the researcher deems most appropriate. Therefore, if output maximization is more plausible than cost minimization an indirect production function should be used.

The plan of the paper is as follows. We first outline the theoretical developments necessary to our approach (included are conditions necessary for consistent aggregation over firms). We then present estimates of an indirect production function and use these estimates to investigate the plausibility of various restrictions on the technology, consistency in aggregation, substitution possibilities in agricultural production, and the effect of expenditure on agricultural input utilization. The paper closes with a discussion of the results and suggestions for future research.  相似文献   
195.
This paper estimates the economic subsides to housing for different groups using the 1988 Joseph Rowntree Memorial Trust sample survey of households.An Olsen type model is used to estimate consumber surplus to households from subsidized housing.These estimates are compared to costs, and housing services in the owner occupier market. Poorer families receive larger benefits than richer families. Transfer efficiency is not high; but the local authority sector receives the greatest benefits from controlled rents.  相似文献   
196.
197.
198.
Utilizing a rich survey data collected in the Southern part of the Philippines, this paper examines the time allocation of wives within the collective household framework by investigating not only the role of socioeconomic factors but also the influence of various intrahousehold power indicators. Analysis of autonomy and finality of intrahousehold decisions discloses that decisions are not unilaterally decided by a single household member, a result which confirms the prediction of collective household framework. Adopting a simple test procedure, this paper also examines which of the competing household models, collective or unitary, best describes these Philippine time-use data. Testing results lend support to the validity of the collective household framework.  相似文献   
199.
Long memory in futures price volatility is a well-documented stylized fact with implications for market efficiency, risk management, forecasting and option pricing bias. The implications of long-memory differ, however, based on whether it is of a ‘fractional’ or of a ‘stochastic’ type. The aims of this article are to determine, in the case of agricultural commodity futures data, which type better describes price volatility and also to evaluate several competing explanations for findings of long memory. The evidence presented here finds little support for three out of four potential explanations, namely, excessive noise in the volatility measure, bias in the long-memory estimator and understated SEs of the long-memory parameter. For the data considered, price volatility appears to be most likely generated by a nonfractional long-memory process such as a stochastic break or stochastic unit root.  相似文献   
200.
Bayesian Model Averaging (BMA) is used for testing for multiple break points in univariate series using conjugate normal-gamma priors. This approach can test for the number of structural breaks and produce posterior probabilities for a break at each point in time. Results are averaged over specifications including: stationary; stationary around trend and unit root models, each containing different types and number of breaks and different lag lengths. The procedures are used to test for structural breaks on 14 annual macroeconomic series and 11 natural resource price series. The results indicate that there are structural breaks in all of the natural resource series and most of the macroeconomic series. Many of the series had multiple breaks. Our findings regarding the existence of unit roots, having allowed for structural breaks in the data, are largely consistent with previous 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