Harnessing the wisdom of crowds: Decision spaces for prediction markets

The increased metabolism of business in the modern world has served to heighten both the frequency and the difficulty of organizational decision making. Practitioners and academics are constantly looking for decision-making mechanisms that can be used to address these challenges. One recently emerged mechanism is prediction markets: a group decision-making tool that uses a market mechanism to rapidly aggregate information held by large, diverse groups of participants. Prediction markets have a number of benefits and have been demonstrably successful in a number of contexts; however, it is important to recognize that they are suited to some types of decisions and contexts but not to others. This article examines the benefits of prediction markets and develops a framework that can be used to identify in which situations prediction markets can be profitably deployed within organizations. It also provides a roadmap for practitioners to use to guide their own organizational deployment of prediction markets.     

基于《企业绩效评价标准值》的医药全行业绩效评价及预测

科学合理的绩效评价是现代企业发展的基础,对行业的发展能起到促进和引导作用。通过计算医药工业全行业、化药制造业、中药材及中成药制造业三个领域全行业综合绩效发现,2008—2014年,中药材及中成药制造业最优,医药工业全行业次之,化药制造业最低。同时通过灰色关联GM（1,1）模型对医药行业绩效进行预测可知,未来五年医药全行业绩效均呈上升趋势。     

基于混沌理论和PSO神经网络的短时交通流预测

交通流预测已成为智能交通的重要组成部分,针对短时交通流的非线性和不确定性,文中根据实际交通流中存在的混沌,利用C-C方法和小数据量法对交通流混沌进行了分析,在交通流混沌时间序列相空间重构的基础上构建了基于粒子群优化神经网络的单点单步预测模型,运用该模型对实际采集的美国加州城市快速路交通流数据进行了仿真研究,结果表明,该预测模型具有较高的预测精度,能够满足智能交通控制和诱导的需求。     

A novel downside beta and expected stock returns

A number of studies have found that the cross-section of stock returns reflects a risk premium for bearing downside beta; however, existing measures of downside beta have poor power for predicting returns. This paper proposes a novel measure of downside beta, the ES-implied beta, to improve the prediction of the cross-section of asset returns. The ES-implied beta explains stock returns over the same period as well as the widely used downside beta, but improves the prediction for future returns due to its high persistence. In the empirical analysis, the widely used downside beta shows a weak relation with future expected returns, but the ES-implied beta implies a statistically and economically significant risk premium of 0.6% per month and explains 0.6% of the variation in the cross-sectional returns. The effect cannot be explained by traditional cross-sectional effects and is different from the CAPM beta, the downside beta in Ang et al. (2006), coskewness, and cokurtosis.     

Accuracy of German federal election forecasts, 2013 & 2017

The present study reviews the accuracy of four methods (polls, prediction markets, expert judgment, and quantitative models) for forecasting the two German federal elections in 2013 and 2017. On average across both elections, polls and prediction markets were most accurate, while experts and quantitative models were least accurate. However, the accuracy of individual forecasts did not correlate across elections. That is, the methods that were most accurate in 2013 did not perform particularly well in 2017. A combined forecast, calculated by averaging forecasts within and across methods, was more accurate than three of the four component forecasts. The results conform to prior research on US presidential elections in showing that combining is effective in generating accurate forecasts and avoiding large errors.     

The wisdom of large and small crowds: Evidence from repeated natural experiments in sports betting

Prediction markets have proved excellent tools for forecasting, outperforming experts and polls in many settings. But do larger markets, with a wider participation, perform better than smaller markets? This paper analyses a series of repeated natural experiments in sports betting. The Queen’s Club Tennis Championships are held every year, but every other year the Championships clash with a major soccer tournament. We find that tennis betting prices become significantly less informative when participation rates are affected adversely by the clashing soccer tournament. This suggests that measures which increase prediction market participation may lead to a greater forecast accuracy.     

Asymptotic and bootstrap prediction regions for vector autoregression

Small sample properties of asymptotic and bootstrap prediction regions for VAR models are evaluated and compared. Monte Carlo simulations reveal that the bootstrap prediction region based on the percentile-t method outperforms its asymptotic and other bootstrap alternatives in small samples. It provides the most accurate assessment of future uncertainty under both normal and non-normal innovations. The use of an asymptotic prediction region may result in a serious under-estimation of future uncertainty when the sample size is small. When the model is near non-stationary, the use of the bootstrap region based on the percentile-t method is recommended, although extreme care should be taken when it is used for medium to long-term forecasting.     

准备金评估的随机性Munich链梯法及其改进——基于Bootstrap方法的实证分析

传统链梯法是未决赔款准备金评估最常用的确定性方法,Munich链梯法基于Mack模型的假设,利用已决赔款和已报案赔款的相关性调整进展因子,有效减少了链梯法分别基于已决赔款和已报案赔款得到的未决赔款准备金之间的差异。本文在系统介绍Munich链梯法的基础上,结合模型假设,提出了两种基于Bootstrap方法的随机性Munich链梯法,并通过精算实务中的数值实例应用R软件加以实证分析。本文的研究对保险公司准备金负债评估的准确性和充足性具有重要参考价值。     

Inefficiency and predictability in the Brexit Pound market: a natural experiment

Exploiting the near-experimental conditions provided by the GBPUSD exchange rate during the Brexit vote of 2016, we quantify a significant delay of the market price in reflecting the increasing probability of a Brexit outcome over the vote counting period. We claim that the Brexit outcome could realistically have been predicted hours before the market adjusted to the outcome. This inefficiency is identified by comparing the market-implied probability of a Brexit outcome with a separate probability, estimated by a standard Monte-Carlo algorithm based on a simple linear regression model, representative of what should have been easily possible in real time. The core of the method is the real-time re-calibration of ex-ante ‘pollster’ predictions for the voting district outcomes by regressing the observed voting results onto them. For comparative purposes, a study of the MXNUSD exchange rate in the 2016 US Presidential Election was done, finding that the market-implied and model-estimated probabilities moved more consistently toward the Trump outcome. Put together, this identifies a somewhat anomalous breakdown in market efficiency in the case of the Brexit vote, which we attribute to its novelty as well as a kind of political bubble and subsequent crash, generated by confirmation bias and social herding.     

企业执行力问题诸说比较分析及研究趋势预测

近年来,全球学术界开始关注企业执行力问题,有必要对国内外执行力研究的理论内容进行系统梳理,并应以企业外部环境的演变为背景对已有的企业执行力相关理论和案例研究结论进行客观的分析和评价,以逻辑推理的形式对执行力理论未来的基本发展态势进行预测。