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   121篇
  免费   7篇
  国内免费   1篇
财政金融   9篇
工业经济   3篇
计划管理   19篇
经济学   38篇
综合类   3篇
运输经济   2篇
旅游经济   4篇
贸易经济   17篇
农业经济   28篇
经济概况   6篇
  2020年   4篇
  2019年   9篇
  2018年   6篇
  2017年   8篇
  2016年   4篇
  2015年   5篇
  2014年   5篇
  2013年   23篇
  2012年   2篇
  2011年   5篇
  2010年   4篇
  2009年   1篇
  2008年   3篇
  2007年   4篇
  2006年   5篇
  2005年   8篇
  2004年   5篇
  2003年   5篇
  2002年   1篇
  2001年   3篇
  2000年   2篇
  1999年   4篇
  1998年   2篇
  1997年   4篇
  1994年   2篇
  1992年   1篇
  1989年   1篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
排序方式: 共有129条查询结果,搜索用时 171 毫秒
1.
通过分析多项式函数f(x)在不同点处的泰勒公式与线性空间基变换的联系,得到了多项式在同点处泰勒公式的一种求解方法。  相似文献   
2.
This paper gives a tree-based method for pricing American options in models where the stock price follows a general exponential Lévy process. A multinomial model for approximating the stock price process, which can be viewed as generalizing the binomial model of Cox, Ross, and Rubinstein (1979) for geometric Brownian motion, is developed. Under mild conditions, it is proved that the stock price process and the prices of American-type options on the stock, calculated from the multinomial model, converge to the corresponding prices under the continuous time Lévy process model. Explicit illustrations are given for the variance gamma model and the normal inverse Gaussian process when the option is an American put, but the procedure is applicable to a much wider class of derivatives including some path-dependent options. Our approach overcomes some practical difficulties that have previously been encountered when the Lévy process has infinite activity.  相似文献   
3.
In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied.  相似文献   
4.
In this paper we introduce a new econometricapproach to analyzing recreational site choicedata, the Dirichlet multinomial model. Thismodel, which nests the standard conditionalmultinomial logit model, can accommodateover-dispersed data and may provide moreefficient estimators of coefficients andconsequent welfare measures than the standardconditional logit model, which is so widelyused in the Random Utility Model approach torecreation demand. We illustrate thisDirichlet approach using a data set of rockclimbers in Scotland, and study the impacts onper-trip consumers surplus of alternativemanagement strategies for popular rock climbingsites. Results show that the Dirichletmultinomial approach produces coefficient andwelfare estimates having smaller samplingvariability in this case. We also compareclassical welfare measures with their posteriorequivalents, which allow for welfare changes tobe dis-aggregated.  相似文献   
5.
Objective: To investigate preferences for fertility treatment from the Australian general population with the aims of calculating the willingness to pay in tax contribution for attributes (characteristics) that make up treatment and for an “ideal” fertility treatment program. We also assessed whether willingness-to-pay varies by the relationship status or sexual orientation of the patient.

Methods: A stated preference discrete choice experiment was administered to a panel of 801 individuals representative of the Australian general population. Seven attributes of fertility treatment under three broad categories were included: outcome, process, and cost. Attributes were identified through published literature, focus group discussions, expert knowledge, and a pilot study. A Bayesian fractional experimental design was used, and data analysis was performed using a generalized multinomial logit model. Further analyses included interaction terms and latent class modeling.

Results: Six of the seven attributes influenced the choice of a treatment program. Under process attributes, individuals preferred: continuity of care of clinic staff, where patients are seen by the same doctor but different nurses at each visit; “alternative” treatments being offered to all patients; and onsite clinic counseling and peer-support groups. Personalization and tailoring of the treatment journey were not important. Among outcome attributes, the improved success rate of having a baby per cycle and significant side-effects were considered important. Cost of treatment also influenced the choice of treatment program. Individual preferences for fertility treatment were not associated with patients’ relationship status or sexual orientation. Latent class modeling revealed sub-groups with distinct fertility treatment preferences.

Conclusion: This study provides important insights into the attributes that influence the preferences of fertility treatment in Australia. It also estimates socially-inclusive willingness-to-pay values in tax contributions for an “ideal” package of treatment. The results can inform economic evaluations of fertility treatment programs.  相似文献   

6.
Multinomial Logit Model has analyzed the relationship between the frequency of visits to recreation areas and the motivational factors affecting the visits. Kastro Environment Preserving Site that is located in the Black Sea coast of Marmara region in Turkey, has been chosen as the site for this study. Kastro bay is a natural park that is visited only for recreational visits. The study has been conducted on a photogenic study group due to the proximity factor of Kastro bay close to Istanbul. Kastro bay is a popular recreational park due to its characteristic advantages such as a 200 m wide and approximately 2.5 km long beach and with its high quality vegetation. The vegetation type includes ash tree, oak tree, black pine, sand lily etc. Kastro bay is also the site for the Mediterranean seals (Monachus-monachus) which are at the level of extinction. Approximately 50,000 visitors visit the region during the months of July and August. It has been concluded that there is high direct correlation between the frequency of visits and the motivational factors. It has been determined that the visits are mostly based on the sea and the ecological tourism.Jel: O13, Q20, Q26, Q51, Q56, Q57  相似文献   
7.
The objective of this study is to determine factors influencing brand preferences of wine consumers in the Marmara region where viniculture and wine production is so important in Turkey. First, the consumers’ preferences survey has been conducted with 1022 persons in the region randomly selected and evaluated. Then, the informative factors influencing brand preferences collected in these surveys have been determined by the multinomial logit model. A lot of independent variables have been used in the multinomial logit model, but, because some independent variables were not found as significant according to Likelihood Ratio test, these variables are not included in the multinomial logit analysis. Six important factors influencing wine brand preferences have been determined. These factors are brand change causes of consumers, occupation of consumers, marital status of consumers, birthplace of consumers, income of consumers and gender of consumers. In addition, whether the wine brand preferences are independent, has been tested with Testing Independence of Irrelevant Alternatives of Hausman. According to this test, it has been found that the wine brand preferences are independent.  相似文献   
8.
This study examines market challenges facing a local agriculture industry in a small island setting. Examination of the Hawai‘i local avocado industry indicates labeling can address the product information gap between consumers and producers, improve market share, and increase import substitution by local products. Currently, local avocados occupy only 33% of market share, compared with 67% captured by imports. Consumer preferences among local labeled, local unlabeled, and imported avocados were analyzed using multinomial logistic regression. Statistical results showed that labels influence consumers’ decisions to buy local or imported avocados, and their preferences were also influenced by sociodemographic variables, avocado characteristics, and purchasing behavior. Key market segments to target and policy implications are also discussed.  相似文献   
9.
The aim of this study is to analyse whether the receipt of public R&D funding determines firm's R&D strategy selection. This issue is crucial, as previous studies have shown that each R&D strategy is associated to a higher, or lower, innovation performance. We consider three R&D strategies – make, buy, make–buy – and three different sources of public funding – regional, state and other (such as EU). The model estimation is performed through a multinomial logit model with random effects with a sample of 457 large firms for the period 1992–2005, taken from the Spanish Survey of Business Strategies. The main finding is that the source of the funding influences whether firms select the make, buy or make–buy strategy. Additionally, because of the panel structure of the sample, we observe that the effect of public funding on the R&D strategy selection lasts longer for state and regional funds than for other funds.  相似文献   
10.
贾社兴  闫晓娜  姜凯 《价值工程》2011,30(12):131-131
工业建筑中,大体积混凝土广泛应用于设备基础,大体积混凝土的质量与结构安全息息相关,大体积混凝土的温度裂缝是主要的质量问题之一。  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