Leveraging a call-put ratio as a trading signal

We examine whether a put-call ratio, derived from a unique set of market data, can be used to predict directional moves in asset prices during various market conditions between March 2005 and December 2012. Our findings show: (1) specific market participant's options trading volume is a predecessor to asset price movements, and (2) portfolios based on the put-call ratio adjusted for four factors Carhart model and transaction costs exhibit abnormal excess returns.     

有偏技术进步视角下中国工业产能过剩的影响因素分析

本文通过将产能利用率在生产侧与消费侧进行分解,测算了中国工业行业产能过剩指数,并考察了技术进步偏向、投资比重等因素对产能过剩的影响效果。研究发现：受生产侧与消费侧产能利用率提升的影响,中国工业总体产能过剩现象呈现下降趋势;生产技术偏向于资本,导致生产过程中偏爱资本投入,加速了投资对产能过剩的恶化程度,这在重工业行业中表现尤为明显。因此,纠正生产过程的要素使用偏好,有利于缓解当前的产能过剩现象。     

科技服务渗透对制造业技术进步的影响

利用世界投入产出表计算制造业细分行业科技服务渗透指数,在此基础上实证分析科技服务渗透对制造业技术进步的影响。结果表明：科技服务渗透促进了制造业技术进步,但作用强度不尽如人意;科技服务业的创新贡献在不同要素密集型制造业差异较大;本土科技服务与进口科技服务对制造业创新绩效都具有显著激励作用,且前者比后者的创新促进效应更显著;科技服务对制造业的创新激励存在明显的本地化效应,本土科技服务与进口科技服务在制造业创新过程中存在互补促进作用,需要进一步强化本土科技服务对进口科技服务的消化吸收再利用能力。     

Estimating Radial Measures of Productivity Growth: Frontier vs Non-Frontier Approaches

In this paper, we propose an alternative econometric framework for estimating and decomposing productivity change that does not require a distribution for inefficiency or the uncorrelatedness between inefficiency and the regressors. We develop our methodology for the input-oriented radial measure of productivity change and establish that this equals the negative of the time change in the log cost function. Our econometric framework is based on a fixed-effects, multiple-output cost frontier, where we decompose productivity change into discrete shifts in the frontier and changes in firm efficiency levels relative to the frontier. We also show that the standard non-frontier specification is nested within our frontier model and thus can produce different estimates of productivity change. Using a panel of twelve US railroads from 1951 to 1975, our estimated cost frontier suggests average annual productivity growth of roughly 0.3 percent, with efficiency change rising then falling over the period. Specification tests reject the non-frontier model, which yields smaller gains in productivity.     

Accounting for Environmental Influences in Stochastic Frontier Models: With Application to International Airlines

The principal aim of this paper is to measure the efficiency of international airlines. We obtain measures of technical efficiency from stochastic frontier production functions which have been adjusted to account for environmental influences such as network conditions, geographical factors, etc. We observe that two alternative approaches to this problem have been proposed in the efficiency measurement literature. One assumes that the environmental factors influence the shape of the technology while the other assumes that they directly influence the degree of technical inefficiency. In this paper we compare the results obtained when using these two approaches. The two sets of results provide similar rankings of airlines but suggest differing degrees of technical inefficiency. Both sets of results also suggest that Asian/Oceanic airlines are technically more efficient than European and North American airlines but that the differences are essentially due to more favourable environmental conditions. Nevertheless, it is among Asian companies that the major improvements in managerial efficiency (technical efficiency with environmental factors netted out) took place over the sample period (1977–1990).     

仓储自动化技术的新进展

本文介绍了国内外仓储技术近几年的发展情况,重点介绍了仓储自动化技术的发展,并对其发展提出了建议。     

中药治疗股骨头坏死的作用机制研究进展

股骨头坏死是骨科难治疾病之一,其具有较高的致残率,严重影响患者身体健康和生命质量,给患者带来极大的心理压力.目前,中药治疗股骨头坏死颇有特色,逐渐被人们认可,故从近年来中药单体、中药经方、自拟方剂3个方面对治疗股骨头坏死的作用机制进行综述,期望为未来中药更加合理有效治疗股骨头坏死提供一定的理论支持.     

Cue usage in financial statement fraud risk assessments: effects of technical knowledge and decision aid use

This paper investigates the effects of technical knowledge and decision aid use on financial statement fraud risk assessments made by directors and students. More extreme fraud risk assessments are made when participants identify and process larger (smaller) numbers of diagnostic (non‐diagnostic) factors, with technical knowledge driving diagnostic factor identification. Significant decision aid‐technical knowledge effects are also found; decision aid use has a detrimental effect on high‐knowledge directors while improving performance in inexperienced, low‐knowledge students. These results suggest that although decision aids can afford gains in performance in inexperienced users, they can have unintended and/or paradoxical behavioural effects on experienced users.     

中国的农业遗产研究:进展与变化

当前中国农业遗产的保护与开发正在不断升温,社会各界关注日增,同时也对农业遗产研究提出了更高的要求。本文首先对中国的农业遗产的概念进行了界定,回顾了中国农业遗产研究兴起的历史背景与各阶段主要特征。在此基础上阐述了近年来中国农业遗产研究在研究重心、研究方法和研究领域等方面的诸多变化,肯定其卓越成果,并指出今后的农业遗产研究不仅应进一步丰富其研究内容、拓展其研究手段,而且要努力从单纯的静态研究向动态研究转化,在关注社会民生与加强农业文化遗产保护和利用方面投入更多的力量。     

Migration and technical efficiency in cereal production: evidence from Burkina Faso

This article uses a double bootstrap procedure and survey data from Burkina Faso in a two‐stage estimation to explore ways in which continental and intercontinental migration determine efficiency in cereal production of rural households. Findings suggest that continental migration has a positive relation and intercontinental migration no relation with technical efficiency. For continental migrant households, migration has removed surplus male labor, a cause for inefficiency in production. Intercontinental migration leads to a gender imbalance in the household, which cannot be compensated for by investments in farm equipment. The failure of intercontinental migration to transform cereal production from traditional to modern is attributed to an imperfect market environment.