ICT-based solution approach for collaborative delivery of customised products

Growing interest on business collaboration motivates today’s industries, especially small and medium enterprises (SMEs) to establish and manage dynamic and non-hierarchical business networks to respond to market opportunities with added business benefits. This business environment requires concurrent work and real-time information sharing between key business partners in order to design and develop customised products. The use of traditional communication media such as e-mail, phone and fax is not satisfactory to get real-time information and is time-consuming and most often ineffective. In such environments, an Information and Communication Technology (ICT)/Web-based technology supports real-time information sharing among networked SMEs for the collaborative design and manufacturing of customised products. This study proposes an innovative ICT platform supporting SMEs collaboration, through Web and the Internet of Things technologies, which follows the Net-Challenge conceptual approach and methodological guidelines for SMEs to form and operate virtual organisations for the collaborative development and delivery of customised products. The ICT Platform was assessed in three different industry domains, namely the textile and apparel, the footwear and the machine tools, respectively. This ICT solution promotes collaboration, with substantial advantages for SMEs including the reduction of costs and delivery time and improvement of the innovation potential.     

权证发行对标的资产交易行为的影响研究

本文用事件研究方法分析了内陆认股权证上市对标的股价和交易量的影响.检验上市交易的总体认股权证样本,发现权证上市后短时期内股价下降和交易量增加;可创设权证的标的资产价格和交易量在发行后短时期内上升.原因可认为权证上市向市场传递了一个利空信息,导致股价在权证上市前大幅下跌;其次卖空限制使股价下降风险得不到有效规避;最后市场规章制度的变化也是其中原因.异常收益检验结果证明内陆资本市场是不完全的.     

集合竞价透明度提高对市场流动性的影响——基于中国股市开盘的实证研究

运用上海A股股票的交易数据,采用事件研究法分析了开盘集合竞价由封闭式改为开放式后市场流动性的变化。通过面板数据回归,检验了开盘交易量比率和连续竞价市场的买卖价差、市场深度、流动性比率和弹性的变化。实证结果表明：在开放式集合竞价机制下,交易者参与开盘的积极性明显提高,连续竞价开始后15min内的市场流动性明显减少。根据不N的交易者对信息揭示的反应不同,得到如下结论：实行开放式集合竞价开盘不仅吸引了更多的交易者参与交易,提高了开盘价格的信息效率,而且缓解了交易者对开盘信息的过度反应。     

The free encyclopedia that anyone can dispute: An analysis of the micro-structural dynamics of positive and negative relations in the production of contentious Wikipedia articles

We consider two rival hypotheses on the emergence of organization in open production communities. According to the first (“reputation hypothesis”), patterns of agreement and disagreement among participants in open production communities are explained by differences in individual reputation for quality of contribution. The reputation hypothesis predicts that participants will tend to agree with more reputable others and disagree with less reputable others thus contributing to establish a stable open production community. According to the second hypothesis (“balance hypothesis”), patterns of agreement and disagreement are explained by membership in sub-communities of “friends” and “enemies.” The balance hypothesis predicts that participants in open production communities will agree mainly with friends and disagree mainly with enemies, regardless of considerations about reputation for the quality of their contributions. In this paper, we examine which one of these hypotheses is more consistent with patterns of positive and negative interaction events observed during the production of the complete set of 1,206 English-language Wikipedia articles officially considered controversial. We specify and estimate new models for signed and weighted relational event networks predicting the probability that a user deletes the contributions of another user – thus expressing personal disagreement – and/or protects the contributions of another user against deletion from third parties – thus expressing personal agreement. In an analysis of positive and negative interaction among Wikipedia contributors consisting of more than 60 million observations, we find strong support for the balance hypothesis and for the predictions of the reputation hypothesis that are more consistent with alter-centric interpretations of social status as conferred by alters through observable acts of deference.     

重大供给冲击对石油市场的影响分析

收集历史上石油市场的重大供给冲击事件,包括委内瑞拉大罢工、伊拉克战争、卡特琳娜飓风、土耳其攻打库尔德、墨西哥湾漏油事件和利比亚战争,选取Brent、WTI现货和期货以及迪拜和阿曼现货等国际主要石油市场数据,建立GARCH模型,分析供给冲击对市场波动性的影响,进一步采用异方差修正的事件分析法考察这些事件对全球主要石油市场收益率的短期影响。研究结果表明,大部分事件会导致事件窗内的方差变大,除伊拉克战争和墨西哥湾漏油事件外,其他事件的事件窗内的累计超额收益显著为正,同一事件下所有市场事件窗内累计超额收益走势一致,重大事件发生的地理区位对邻近市场的收益率的影响更大。对实证结果进行经济解释,针对不同的石油市场参与者给出相应的政策建议。     

Analyzing panel count data with a dependent observation process and a terminal event

Panel count data occur in many fields and a number of approaches have been developed. However, most of these approaches are for situations where there is no terminal event and the observation process is independent of the underlying recurrent event process unconditionally or conditional on the covariates. In this paper, we discuss a more general situation where the observation process is informative and there exists a terminal event which precludes further occurrence of the recurrent events of interest. For the analysis, a semiparametric transformation model is presented for the mean function of the underlying recurrent event process among survivors. To estimate the regression parameters, an estimating equation approach is proposed in which an inverse survival probability weighting technique is used. The asymptotic distribution of the proposed estimates is provided. Simulation studies are conducted and suggest that the proposed approach works well for practical situations. An illustrative example is provided. The Canadian Journal of Statistics 41: 174–191; 2013 © 2012 Statistical Society of Canada     

Multivariate Failure Time Analysis when only the Time to First Failure is Observed

We propose a log-linear mixed model to assess covariate effects on the unobservable, catheter-related time-until-infection (TUI), utilizing the observable time-until-first-infection (TUFI). The model assumes that both log (TUI) and the common (random) patient effect follow an extreme value distribution, and TUIs of the same patient are conditionally independent. This model enables the assessment of covariate effects on TUI, accounting for both patient-level (age) and catheter-level (e.g., difficulty of insertion) covariates and the within-patient correlation. The efficient likelihood estimators of fixed-effects and scale parameters of random effects are shown to be consistent and asymptotically normal and appear to perform well in simulations. The methods are illustrated using an example.     

1957-1960年间的《长生殿》讨论：人性论及其批判

1957-1960年间的《长生殿》研究仍主要集中于思想主题。在此期间,沉寂三年的爱情主题说重出江湖并再次成为焦点。其支持者从人性论、典型论角度对这一主题说的申辩所引发的讨论,使《长生殿》思想主题的研究超越文本研究的范畴,而触及文艺批评的基本理论问题,本来有可能促进《长生殿》讨论的深入发展。但政治风向与思想氛围的变化,改变了论争的基调,学术讨论再次演变成了思想批判。