Tick size and market quality: Simulations based on agent‐based artificial stock markets

This paper investigates the way that minimum tick size affects market quality based on an agent‐based artificial stock market. Our results indicate that stepwise and combination systems can promote market quality in certain aspects, compared with a uniform system. A minimal combination system performed the best to improve market quality. This is the first study to analyse tick size systems that remain at the theory stage and compare four types of system under the same experimental environment. The results suggests that a minimal combination system could be considered a new direction for market policy reform to improve market quality.     

川西北高原藏区农村贫困化分异机制探测

[目的]客观揭示农村贫困化地域分异机制,为科学推进川西北高原藏区精准扶贫创新途径、综合战略和认真贯彻落实中央治藏方略提供参考依据。[方法]应用地理探测器模型、GIS空间分析与地统计方法等方法,探测川西北高原藏区贫困村单位面积GDP分异的主导因素,揭示农村贫困化分异机制,提出不同贫困化地域类型的扶贫政策措施。[结果]影响川西北高原藏区农村贫困化分异的主导因素包括到主要交通道路距离、归一化植被指数(NDVI)、土地利用、年均温度和海拔高程等,各因素对贫困村经济发展分异的解释力分别为80. 76%、12. 82%、8. 82%、5. 45%和3. 96%;贫困村经济发展贫困化的分异机制存在明显差异,可归纳为交通区位约束型、自然环境约束型和经济区位约束型等三大类型;农村贫困化驱动机制下的贫困村精准扶贫政策措施亟需因地制宜、科学推进、讲求实效,有序推进精准扶贫战略。[结论]精准扶贫应分类指导、重点突破,尤其加强贫困村交通、水利、公共基础设施建设和特色农牧业产业培植,注重多种扶贫模式的综合集成。     

名山风景区风景特质理论体系及其实践 ——以武当山为例

名山风景区“人与天调”的风景系统代表了中国独有的山岳文化现象和山水相融的总体特征。在风景自然和文化整体性视角下研究风景系统的形态、类型及其形成原因和规律，分析了风景资源评价和风景特质评价的互补性；构建了“相-制-理”的名山风景区风景特质理论及其实践框架。以武当山为例，探索“以脉绘景”的风景特质之相、“山川流峙”的风景特质之制以及“因脉而成”的风景特质之理。最后总结了风景特质理论作为形态学理论、作为图谱理论、作为地脉文脉认识论实践的整体性特点及其应用前景。     

城市道路桥梁工程施工技术要点

整个道路桥梁工程施工质量从很大程度上受到施工技术合理性影响.城市道路桥梁关系着国民日常出行便捷与安全,为此需要做好施工技术合理选择,确保落实各项技术,保证施工项目质量,加强成本控制.通过明确道路桥梁施工技术要点有助于落实施工技术方案,有助于工程质量优化,促进企业未来发展.为此,应当在明确道路桥梁工程施工要点基础上,加强各项技术应用,并且加强施工质量管控,建设优质项目.     

城市道路桥梁工程施工技术要点

整个道路桥梁工程施工质量从很大程度上受到施工技术合理性影响.城市道路桥梁关系着国民日常出行便捷与安全,为此需要做好施工技术合理选择,确保落实各项技术,保证施工项目质量,加强成本控制.通过明确道路桥梁施工技术要点有助于落实施工技术方案,有助于工程质量优化,促进企业未来发展.为此,应当在明确道路桥梁工程施工要点基础上,加强各项技术应用,并且加强施工质量管控,建设优质项目.     

本科生导师制的优化研究:多学科交叉视角

本科生导师制往往由于受专业的限制,不能充分发挥作用.高校应当摒弃专业和学科限制,以兴趣导向、自由选择的方式建立跨学科的本科生导师制,提高导师指导效果,激发学生兴趣,提升学生综合素质.     

Capital asset pricing model in Portugal: Evidence from fractal regressions

We examine risk profiles of the Portuguese stock market index component stocks using a novel approach to the classical capital asset pricing model (CAPM). Specifically, we estimate the CAPM via fractal regressions that allow studying the marginal effects at selected scales. In this way, we can reveal whether the risk is perceived differently by market participants with different investment horizons. Apart from the analysis itself, we provide new statistical insights into the issue of separating and comparing the scale-specific effects with statistical validity. We find several stocks deviating from an expected risk perception homogeneity across investment horizons. This is true for both analysed periods, i.e. before and after the global financial crisis. There are also several stocks that changed their relationship to the market portfolio in between, which has strong implications for possible portfolio construction. The proposed methodology is not limited to financial topics but can be used in any discipline where the scale-specific marginal effects might be of interest.     

The Structure of Problem Structuring Conversations: A Boundary Games Approach

One of the questions associated with facilitated problem structuring is how the micro level of actors’ multimodal communications, contributes to the emergence of a macro level, framing the possibilities for action in a workshop. This paper shows a way to study this macro level, building the visualization of the conversations’ structure starting from a boundary games theory micro analysis of the interactions. Our empirical evidence comes from following a group of academic consultants working to define a value proposition for their activity. We focus on analyzing two out of nine workshops that were felt diametrically opposite in terms of facilitation and achievements. Moving from the micro towards an upward level, three configurations building the structure are identified—shifting, branching and converging. The work carried out allows us to: (1) visualize the structure of conversations in a problem structuring context, (2) highlight the role of multimodal communications in building the conversations and (3) construct an interpretation bridging the micro and macro readings of a workshop. This knowledge is useful for facilitators guiding the dynamic of a workshop and for researchers looking forward to understanding how micro level interactions build higher levels of the social phenomenon of intervention.     

Bayesian Inference in Spatial Sample Selection Models

In this study, we consider Bayesian methods for the estimation of a sample selection model with spatially correlated disturbance terms. We design a set of Markov chain Monte Carlo algorithms based on the method of data augmentation. The natural parameterization for the covariance structure of our model involves an unidentified parameter that complicates posterior analysis. The unidentified parameter – the variance of the disturbance term in the selection equation – is handled in different ways in these algorithms to achieve identification for other parameters. The Bayesian estimator based on these algorithms can account for the selection bias and the full covariance structure implied by the spatial correlation. We illustrate the implementation of these algorithms through a simulation study and an empirical application.