Simplifying The Big Mac Index

The Economist magazine recently introduced a major innovation to its famous Big Mac Index of currency values by adjusting for differences in incomes of countries. A recent paper (O'Brien and Ruiz de Vargas, 2017 , OR) explains clearly the workings of the new index, something overlooked by The Economist. The current article draws on OR to suggest an alternative formulation that is attractive in its simplicity.     

“巨无霸”和“巨无霸”思维方式

美国人大多以汉堡为普通食品,供求关系中“求”的力量大;中国人大多则视汉堡为偶尔休闲食品,“求”的力量小。供求关系的不同,价格自然就会不同     

The Quest for Quality: A Quality Adjusted Dynamic Regulatory Mechanism

In situations where quality is fixed, the widely used RPI‐X regulatory mechanism has a number of desirable properties, such as convergence to a second best optimum. Theoretical analysis of this mechanism in the case of endogenous quality is limited and therefore regulators have typically imposed constraints on the firm's quality choice in ad hoc manners, either by mandating quality levels, or by including quality adjustment factors in the RPI‐X mechanism. In this paper, we construct the rigorous theoretical counterpart of these manners of including quality measures in the constraints faced by a regulated firm. This mechanism converges to second best optimum. It works by offering the firm trade‐offs between prices and qualities based on the choice it made in the previous period; however, reflecting the practical problem valuing quality, the informational requirement to select these trade‐offs appropriately is qualitatively stronger than in the fixed quality case. Moreover, even when the informational problem can be overcome, we identify a further potential pitfall in the approach taken in practice by regulators, and show that, in order to avoid it, the regulated firm should be subject to an additional constraint, which we label the distance constraint, and which can be interpreted as requiring the firms to choose prices and qualities within a band in every period.     

The Range Adjusted Measure (RAM) in DEA: Comment

Journal of Productivity Analysis -     

The sentimental city: the lost urbanism of Pierre Mac Orlan and Guy Debord

Behind a high stonewall surrounding a rural farmhouse in Auvergne, Guy Debord, the ex‐Situationist theorist and activist, retreated. The grungy, cheap‐thrill Parisian urbanism of his youth was no more. Paris had died in his arms of a fatal illness that has seen off other great cities. Economic forces and planning initiatives had assassinated his rebel underworld, and culprits are still at large, still awaiting trial in the people's court. This essay embraces Debord the other side of the wall, dialoging with Pierre Mac Orlan, one of his favorite novelists. In so doing, we enter the phantasmal zone of the sentimental city, the city both real and make‐believe, defunct and yet‐to‐be. Mac Orlan's ideas about passive and active adventuring are explored here, to unlock the Pandora's box of Debord's urbanism. The essay approaches the capitalist city with a poetic gloss and reveals a realm richer and deeper than most social scientific urban research can grasp. Alongside Mac Orlan, Debord retraces his steps through urban ruins, and recaptures an everyday melancholy of backstreets and damaged people, of twilight nooks and crannies and shadowy bars. In Debord's sentimental city, it isn't so much the past that one regrets as the future. Derrière un haut mur de pierre entourant une ferme d'Auvergne, s'est retiré Guy Debord, l'ancien théoricien et militant situationniste. L'urbanisme parisien minable et décadent de sa jeunesse n'existait plus. Paris était mort dans ses bras d'une maladie désastreuse qui a emporté d'autres grandes villes. Forces économiques et initiatives d'aménagement ont assassiné son milieu rebelle et les coupables courent encore, dans l'attente d'un procès populaire. Cet essai voit Debord de l'autre côté du mur en train de dialoguer avec Pierre Mac Orlan, l'un de ses écrivains favoris. Ainsi, nous entrons dans l'illusion de la ville sentimentale, ville à la fois réelle et imaginaire, défunte et survivante. Les idées de Mac Orlan sur l'aventurier actif et passif y sont examinées afin d'ouvrir la boîte de Pandore de l'urbanisme selon Debord. L'approche de la ville capitaliste revêt un vernis poétique, révélant un univers plus riche et plus profond que ce qui peut être saisi par la plupart des recherches urbaines en sciences sociales. Aux côtés de Mac Orlan, Debord revient sur ses pas, traversant des ruines urbaines, retrouvant une mélancolie au quotidien des bas‐quartiers et d'une pègre abîmée, des coins et recoins obscurs et des bars mal éclairés. Dans la ville sentimentale de Debord, ce n'est pas tant le passé que l'on regrette, mais plutôt l'avenir.     

段永基 消失的大佬

他在文革中度过了自己的清华人生。他的人生充满了悲剧意味,在巅峰时期,他曾掌控三大上市公司,创造过产业辉煌;但他也无数次陷入败局,每次都是竭尽全力,才勉强得以脱身。他是中关村最知名的老企业家,骨子里却像一个有几分赌徒气质的投机商人;他对朋友很讲义气,但也善玩权术。有人尊称他“中关村村长”,也有人戏称他为“赌徒”。     

基于大数据的水资源系统分析与决策方法研究

针对水资源数据呈现的大数据特性,研究大数据驱动的水资源系统分析与决策关键技术方法。在分析传统方法局限性的基础上,提出"数据+规律+调控"的水资源系统分析与决策新模式,论述了制约水资源大数据分析应用的主要问题,总结提出了实现水资源系统大数据分析的关键技术,以期为实现大数据驱动的水资源系统分析与调控提供参考。     

The Range Adjusted Measure (RAM) in DEA: A Response to the Comment by Steinmann and Zweifel

Journal of Productivity Analysis -     

袁旭小人物创大财富

虽然只有26岁,但公司员工都称他为“老袁”。他就是四川迅游网络科技有限公司的总裁,管理着逾50名员工,这个“玩”出来的公司盈利上千万,已达到冲刺创业板的条件,而拿到亿元投资后,袁旭及公司一夜成名。     

纳米技术:小中见大的质量新领域

您见过苹果的iP0d nano（纳米）随身听吗？尽管它已经非常薄了,但是它仍不是真正的纳米尺度。术语“纳米”指米制度量体系的十亿分之一。因此,一个直径为一纳米的物质指它的大小只有1米的十亿分之一（即104米）。iPod的厚度（苹果愿意称它为薄度）大约是7百万纳米。如果把它缩小为1纳米,就相当于把地球直径缩小到您的臂展长度。     

无线搜索“改革派”

“人家投上5000万美金,1000个人就能把你砸死。这种话我听N个人说过。真的吗？谁呀？”宜搜是无线搜索领域唯一可与百度、谷歌等搜索巨头PK的公司,而且汪溪无畏无惧     

A Better Understanding of Granger Causality Analysis: A Big Data Environment

This paper aims to provide a better understanding of the causal structure in a multivariate time series by introducing several statistical procedures for testing indirect and spurious causal effects. In practice, detecting these effects is a complicated task, since the auxiliary variables that transmit/induce indirect/spurious causality are very often unknown. The availability of hundreds of economic variables makes this task even more difficult since it is generally infeasible to find the appropriate auxiliary variables among all the available ones. In addition, including hundreds of variables and their lags in a regression equation is technically difficult. The paper proposes several statistical procedures to test for the presence of indirect/spurious causality based on big data analysis. Furthermore, it suggests an identification procedure to find the variables that transmit/induce the indirect/spurious causality. Finally, it provides an empirical application where 135 economic variables were used to study a possible indirect causality from money/credit to income.     

A Quality Information Benchmarking Methodology: A US Banking Industry Empirical Study

Information is itself a product that customers and staff in any organization consume. Like any product the quality of information can be measured and compared in most industries. This paper presents an application of an information quality measuring methodology adapted and applied for the first time in the US banking industry. An empirical study is used to attest to the informational efficacy of the methodology. Results of the study reveal that the proposed methodology can be used to identify quality differences between differing banking institutions and differing dimensions of information quality as well as a quality benchmarking procedure.     

基于流动性调整CAViaR模型的风险度量方法

本文提出了流动性风险度量的一个新的方法,流动性调整的CAViaR模型。该模型能够直接反映资产流动性的变动对未来风险的影响,并在此基础上计算资产未来经过流动性调整的风险VaR,从而使投资者能够更好地管理风险,尤其是流动性风险。实证研究表明,该模型能够较好地刻画中国股市流动性风险的动态变化特征;并且发现股票流动性的大幅下降通常导致未来风险明显加大,且正向流动性下降所带来的风险往往较负向流动性要更大,因此更值得投资者关注。     

Measuring Corporate Environmental Performance: A Methodology for Sustainable Development

Assessing corporate environmental performance (CEP) that is both comprehensive and consistent with sustainable development both for society and companies, while at the same time taking heed of the facts and interests of each stakeholder, is not a simple feat. Due to the multidimensional character of the sustainability concept, several questions must be considered in the evaluation process: (i) the qualitative nature of indicators and the complexity of developing a synthetic index; (ii) the difficulty of choosing properly statistical techniques for aggregation and (iii) the difficulty of introducing stakeholders’ preferences in the assessment models. This paper is an attempt to address this challenge by developing a framework for the assessment of CEP, based on the application of a fuzzy multi‐criterion decision‐making (MCDM) method. To achieve positive scores in a CEP assessment, an organization should be strategically committed and engage in environmental management and governance structures that are translated into good results in terms of both engagement and operational performance. Unless such premises are explicitly incorporated into the assessment criteria, the results would reveal that the CEP measurement could not be brought into a line with an earnest ambition of achieving true sustainable development. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment     

2007年度最负责任的企业：IBM中国从蓝色巨人转向绿色巨人

企业承担社会责任是企业自身发展的需要。谋求自身发展是企业的无职,追求经济效益是企业发展的重要目标,但不是唯一目标。履行和承担好社会责任也同样应该是企业发展的重要目标。这两个目标同时也是社会衡量企业发展的标准。两个标准的结合反映出企业发展的水平和持续发展的潜力。这是因为,企业是在社会中发展的。企业的发展离不开社会。另一方面,社会是由包括企业在内的各种主体组成的,社会的进步包括企业的发展,也需要企业的发展来推动。经济社会发展了。可以为企业提供更大的发展空间和创造更好的发展环境,从而进一步促进企业自身的发展。同时,企业的发展使它有更大的能力来履行和承担社会的责任。更好地促进经济社会的发展。     

基于状态空间模型的中国季度GDP季节调整(1996～2009年)

中国迄今为止尚未公布包括季度GDP在内的经季节调整的经济指标数据,这不仅不利于对中国宏观经济运行监测,也无法满足国际比较的迫切需要。本文对中国1996年一季度至2009年四季度的实际GDP构建基于状态空间形式的季节调整模型,通过卡尔曼滤波递推算法对状态向量的各分量进行了最优估计、平滑和预测,并对超参数进行了极大似然估计。在此基础上分析了这一期间中国GDP的主要季节和趋势特征,并计算出了季节调整后的季度环比增长率指标用来分析和监测经济走势,鉴别趋势拐点,制定相关经济政策。最后通过与国际通用的TRAMO-SEATS季节调整模型的对比发现其优越性。     

A Match Made in Heaven: A Marginalized Methodology for Studying the Marginalized

Marginalization consists in not taking others into account on any number of valued outcomes, resulting in powerlessness, ignorance, poverty, illness, insecurity, and other manifestations of devaluation. Two illustrations are presented, including a brief summary of Q methodology, an innovation in factor theory that was marginalized by 20th century developments in psychometrics but has more recently experienced a revival in interest, and which is particularly suited to illuminating and clarifying perspectives, including those of marginalized populations. The procedures associated with Q methodology are demonstrated in terms of clarifying the goals of a Central American initiative to foster development. A second illustration focuses on the applicability of Q methodology in revealing marginalized tendencies within single individuals. A variety of other recent and current applications are briefly summarized.