Objective methods for graphical structural learning

Graphical models are used for expressing conditional independence relationships among variables by the means of graphs, whose structure is typically unknown and must be inferred by the data at hand. We propose a theoretically sound Objective Bayes procedure for graphical model selection. Our method is based on the Expected-Posterior Prior and on the Power-Expected-Posterior Prior. We use as input of the proposed methodology a default improper prior and suggest computationally efficient approximations of Bayes factors and posterior odds. In a variety of simulated scenarios with varying number of nodes and sample sizes, we show that our method is highly competitive with, or better than, current benchmarks. We also discuss an application to protein-signaling data, which wieldy confirms existing results in the scientific literature.     

基于SCP范式的中国乳业市场绩效的实证分析

基于SCP范式的理论对我国乳业市场结构和市场行为的各项指标以及对市场绩效的影响进行实证分析,发现市场结构作用于市场行为并最终影响市场绩效,为企业在调整市场结构以提高市场绩效方面提供可借鉴的理论和政策建议。研究结果表明:①我国乳业行业规模经济效益越来越显著,行业进入壁垒提高,市场结构逐渐向中高度寡占型转变;②我国乳业的市场绩效与市场集中度、行业规模之间的相关关系通过显著性检验;③乳制品行业内各乳企之间的产品差异化不明显,技术程度有待加强。     

Limited attention,share repurchases,and takeover risk

We hypothesize that announcing open market share repurchases (OMRs) to counter negative valuation shocks reveals repurchasing firms’ lost growth opportunities or underperforming assets to potential bidders, making them more likely to become takeover targets. This also leads their investors to face higher takeover risk, a systematic risk associated with economic fundamentals that drive takeover waves, as proposed by Cremers et al. (2009). Indeed, we find that repurchasing firms tend to face higher takeover probability in the first few years following their OMR announcements, and that the increase in takeover risk can largely explain their post-announcement long-run abnormal returns documented in the literature. The increase in takeover risk is larger for smaller firms, firms with poorer pre-announcement stock performance, and those attracting more attention of market participants. Our results suggest that OMRs, which are used by many firms to counter undervaluation, could make the firms more sensitive to takeover waves and raise their cost of equity capital.     

“一带一路”沿线国家贸易开放与劳动收入份额

基于1990~2014年的跨国数据,实证研究贸易开放对"一带一路"沿线国家劳动收入份额的影响。分析发现,"一带一路"沿线国家的劳动收入份额均值下降了5%以上。采用固定效应模型和工具变量法的实证分析表明,整体上贸易开放抑制了"一带一路"沿线国家的劳动收入份额。进一步将"一带一路"沿线国家按照经济发展水平、要素禀赋、制度环境分组研究发现,贸易开放对高经济发展水平国家、资本密集型国家、资源密集型国家、制度环境良好国家的劳动收入份额具有显著负影响,但是对于低经济发展水平国家、劳动密集型国家、制度环境不佳国家的劳动收入份额具有显著正效应。而向中国贸易开放能够提高"一带一路"沿线国家的劳动收入份额,特别是对低经济发展水平国家的积极影响较强。上述实证结果具有稳健性。在此基础上提出了相应的政策建议。     

焦点企业知识存量对联盟组合分裂断层的影响：知识转移效率的中介作用

运用断层理论，从知识获取和关系治理角度，分析焦点企业知识存量如何影响联盟组合分裂断层及分裂断层形成机理。基于焦点企业知识存量、分裂断层、知识转移效率、情景嵌入性之间的关系理论模型框架，认为焦点企业知识存量能够影响联盟组合分裂断层，其中，知识转移效率在这一过程中发挥中介效应，情景嵌入性发挥调节效应。结果发现：焦点企业知识存量与分裂断层之间存在显著负相关关系；知识转移效率能够部分中介焦点企业知识存量与分裂断层之间的关系；情景嵌入性能够正向调节焦点企业知识存量与知识转移效率之间的关系。     

环境与就业维度下出口商品结构优化——以江苏为例

利用计量方法从环境和就业这两个指标来考察江苏出口商品结构优化,其中环境指标主要是通过碳排放指标来体现的。通过研究发现江苏九大类出口商品在环境和就业指标上都无此消彼长现象,其中对两指标都具显著影响力的为机械及运输设备,化学品及有关产品和按原料分类的制成品这两类出口商品仅对环境有着显著影响力,对就业不具显著影响力,至于其他种类的出口商品则对环境和就业这两个指标都不具显著影响力,最后得出江苏出口商品结构优化的最明确方向,即大力促进机械及运输设备的出口,抑制化学品及有关产品和按原料分类的制成品这两类出口商品的出口。     

城市化、政府财政支出、就业所有制结构与城乡收入差距

基于1985-2012年的数据,建立以城市化、政府财政支出、就业的所有制结构为内生变量的向量误差修正模型,并且用协整检验考察城市化水平、政府财政支出、就业的所有制结构的长期均衡与短期动态关系。实证分析发现:四者不仅存在长期的均衡关系,而且存在短期动态关系。具体而言,城市化、政府财政支出、就业的所有制结构在长期会扩大城乡收入差距,在短期则会缩小城乡收入差距。     

The impact of IT-enabled customer service systems on service personalization,customer service perceptions,and hotel performance

Customer service is a critical element of a hotel's strategy and an important lever for differentiation of the hotel's offer. Over the last two decades, information systems have contributed to the transformation of customer interactions, enabling an unprecedented scale and scope of service personalization in the tourism industry. This paper reports the results of a mixed method study in a hotel that offers three contributions to the development and refinement of IT-enabled service personalization theory. It explores the role of signifiers in the design of customer service systems, showing that they significantly increase customer preference elicitation during the learning phase of the service personalization process. It then demonstrates that improved preference elicitation translates into higher customer service evaluations and value perceptions of the hotel. Finally, our study shows that IT-enabled service personalization creates financial benefits for the hotel via revenue share-shift from costly intermediated to direct distribution channels.     

Is corporate payout taxation a long run phenomenon? Evidence from international data

This paper examines whether dividend and capital gains taxation influences corporate payout policy using the country level data of 21 countries in panel versions of time series models. We find that dividend relative to capital gains tax penalty is cointegrated with corporate payouts (dividends and share repurchases) i.e. corporate payout taxation may be a long run phenomenon. Further, the cointegrating vector estimates are largely consistent with the traditional view of dividend taxation whereby the tax penalty discourages dividends, while the estimates give limited support to the premise that firms substitute dividends for share repurchases in response to an increase in dividend tax penalty. Long run causality also operates between the tax penalty and payouts in the error correction models. Additionally, dividend tax appears to be more influential than capital gains tax on dividend payout decisions. Lastly, taxation affects dividends more significantly in countries with high investor protection.     

新医药产业协同创新结构考察

协同创新的本质是创新系统的结构构建,各创新要素之间的联结和相互作用机制决定了协同创新系统的效率。本文以江苏新医药产业为例,从创新网络的节点和创新资源两个方面分析了新医药产业协同创新的结构,并从创新网络的结构特征归纳了新医药产业协同创新的类型,最后提出应如何通过构建产业协同创新的结构来优化创新系统的效率。