我国风险投资事业的法律制度建设研究

法律制度作为制度环境的重要组成部分,对社会的制度安排的演化和创新起着或制约或推动的作用。本文通过对风险投资这种金融创新的制度经济学分析,列举了目前我国法律制度供给与风险投资制度安排需求的冲突与滞后,指出政府进行法律制度的创新才是发展风险投资事业的关键。     

Feeding management of dairy cattle affect grassland dynamics in an alpine pasture

The effect of different supplementary feeding rates for grazing cattle on high-altitude pastures dynamics was evaluated. A field experiment was carried out during three years in a subalpine pasture area of the Eastern Alps. The investigated pasture area was 40?ha, located between 1820 and 2230?m?a.s.l. Two paddocks were chosen in the experiment and two herds of 12 cattle each were kept in the two enclosures for 5 weeks. For the first herd (HS), the supplementary feeding rate was 4.8?kg?OM?head^?1 per day, while for the second herd (LS), the rate was 1.6?kg?OM?head^?1 per day. The amount of herbage consumed by each cattle was determined using the n-alkane technique. To monitor the pasture vegetation dynamics, eight metal exclusion cages were placed in each paddock to determine herbage growth, utilization rates, vegetation composition and animal grazing selectivity. Grazing behaviour of dairy cattle, in terms of herbage intake and species selection was affected by the different feeding rates. Cattle grazing Paddock HS consumed 1.9?kg?OM?day^?1 of herbage less than Paddock LS. In the LS paddock, cattle grazed higher phytomass rates. When the animals were fed by higher concentrate rates, a more selective grazing seemed to significantly increase the pasture necromass component. The lower grazing selectivity favoured the development of species as Nardus stricta and Deschampsia caespitosa, which are well known for their low palatability. Distinct vegetation dynamic patterns were observed, with a reduction of hair grass and an increase of legumes in the Paddock LS.     

Pricing a rural development program: uncertainty,indifference, and protest behaviors

This article presents an econometric approach to modeling uncertainty, unwillingness to pay, and protest behavior in contingent valuation studies. For that purpose, a mixture model with sample selection is developed for a multiple‐bounded uncertainty elicitation format. The proposed theoretical framework is applied to evaluate the social welfare impact of implementing a sustainable rural development program. Results show that a “naive” analytical approach that excludes protesters from the analysis would result in significantly higher willingness to pay estimates for those individuals who favor the implementation of the program and agree to reveal their true reservation prices.     

A proposed configurable approach for recommendation systems via data mining techniques

This study presents a configurable approach for recommendations which determines the suitable recommendation method for each field based on the characteristics of its data, the method includes determining the suitable technique for selecting a representative sample of the provided data. Then selecting the suitable feature weighting measure to provide a correct weight for each feature based on its effect on the recommendations. Finally, selecting the suitable algorithm to provide the required recommendations. The proposed configurable approach could be applied on different domains. The experiments have revealed that the approach is able to provide recommendations with only 0.89 error rate percentage.     

A novel decision support model for satisfactory restaurants utilizing social information: A case study of TripAdvisor.com

Decision support models for satisfactory restaurants have attracted numerous researchers' attention. Many extant models do not consider the active, neutral and passive information in online reviews all at once. Moreover, they ignore the effect of interdependence among criteria on tourists' decision-making. To cover these defects, this study proposes a restaurant decision support model using social information for tourists on TripAdvisor.com. The model introduces fuzzy sets to denote online reviews and utilizes Bonferroni mean to consider interdependence among criteria. Furthermore, it uses a novel similarity measurement which can handle sparse data in fuzzy environments. To validate the model, we conduct a case study of TripAdvisor.com which compares the proposed model with four other models. The performance of each model is evaluated by the metric called the mean absolute error. The study shows that the proposed model can effectively support tourists' decision-making and it performs better than the other four models.     

技术演化Logistic模型的扩展:多种技术创新演化的选择过程分析

典型的技术演化Logistic模型描述的是当存在两种新、旧技术的竞争时,单种创新的技术随时间的演化而扩散演化的轨迹,其缺陷是没有对多种创新技术同时作用进行分析。本文考虑一个改进的创新技术的扩散模型,拓展Logistic模型的解释空间,用技术适应度、新技术选择“尝试努力”时所运行的时间、平均尝试次数、“尝试努力”成功次数的平均概率等指标,来考察在一个固定的技术选择空间内,多种技术演化的随机寻优轨迹和寻优难度;从而在一定程度上为拓展技术选择空间引入新技术,不断进行技术创新提供理论解释。     

从公司治理视角看会计政策选择

在介绍公司治理和会计政策选择的基本概念及其相互关系的基础上,重点阐述了各公司治理相关利益主体对公司治理机构中的制衡关系及其对公司会计政策选择的影响,最后提出从公司治理入手,提高会计政策选择的公允性。     

政府会计的逆向选择模型分析

作为国家进行公共财政管理、提高财政透明度的有力手段,政府会计已经日益受到政府和相关人士的重视,但人们的注意似乎都集中在如何建立完善的政府会计体系上,对于"为什么要建立政府会计体系"这一基本的理论却研究很少。本文就以博弈论为理论出发点,建立了政府与纳税人之间的逆向选择模型,讨论了政府和纳税人之间在信息不对称情况下将出现的逆向选择问题,针对这一问题提出两个解决方法——信号传递和信号甄别,结合这两种方法,得出"无论是政府还是纳税人,都对建立完善的政府会计体系有更高的要求"的结论,于是,政府会计才会应运而生。本文试图从博弈论的角度论证政府会计之所以存在的依据。     

Economic natural selection in Bertrand and Cournot settings

We study economic natural selection in classical oligopoly settings. When underlying pure strategies consist of a finite number of prices, convex monotonic dynamics always converge under a weak condition to the smallest price in the support of the initial state that exceeds marginal cost. When underlying pure strategies consist of a finite number of quantities, monotonic dynamics always converge under a specific condition to a quantity equal or similar to classical Cournot equilibrium.     

Elements of Publicness in Urban Transit

This paper examines the claim that Veblen's theory of cultural evolution has generalized Darwinian principles to socioeconomic phenomena. Our argument takes place in the debate around "generalized Darwinism" in evolutionary and institutional economics. We claim that Veblen frequently relied on the concept of selection and considered institutions both as units and as factors of selection. We also argue that some of Veblen's insights can be clarified by expressing them in evolutionary-game theoretic terms. Thus, we suggest a close connection between the ontological framework of generalized Darwinism and the technical study of evolutionary phenomena through evolutionary game theory.