Performance of French intensive care units: A directional distance function approach at the patient level

By using a novel adaptation of the free-disposable hull analysis of productivity, we assess the medical and technical efficiency of patient care in 25 Parisian intensive care units (ICUs) during 2000. The robust free disposable hull (RFDH) as defined by [Cazals et al., 2002. Nonparametric frontier estimation: a robust approach. Journal of Econometrics 106, 1–25] reduces the impact outliers may have on findings by employing Monte-Carlo techniques and repeated sample selection. Among our key findings, there was no overall significant correlation between medical and technical efficiencies for all the ICUs, therefore performing well in one does not guarantee good performance in the other. We also found that over 80% of inefficiency is concentrated in less than 20% of the sampled patients.     

An extension of the multi-output state-contingent production model

This paper presents new developments on the state-contingent theory of production under uncertainty with stochastic prices. Our main purpose is to generalize the usual finite discrete state-contingent production model to infinite dimensional, possibly uncountable spaces which look like a more realistic framework. Usual duality results are established in this general context, shedding some light on the links between risk-neutral probabilities and shadow prices. A direct generalized production risk premium is defined and is shown to be independent of the inputs level when the technology is output translation homothetic. In such a case, the technology exhibits constant absolute riskiness. We thank Bob Chambers for his helpful comments.     

Out‐of‐sample stock return predictability in emerging markets

This article builds on the widely debated issue of stock return predictability by applying a broad range of predictor variables and comprehensively considering the in‐sample and out‐of‐sample stock return predictability of ten advanced emerging markets. It compares forecasts from models with a single predictor variable, multiple predictor variables and a combination forecast approach. The results confirm the findings of Welch and Goyal (2008) for US data that only a limited number of individual predictor variables are able to deliver significant out‐of‐sample forecasts. However, a combination forecast approach provides statistically and economically significant out‐of‐sample forecast results.     

Very fast money: High-frequency trading on the NASDAQ

This paper provides evidence regarding high-frequency trader (HFT) trading performance, trading costs, and effects on market efficiency using a sample of NASDAQ trades and quotes that directly identifies HFT participation. I find that HFTs engage in successful intra-day market timing, spreads are wider when HFTs provide liquidity and tighter when HFTs take liquidity, and prices incorporate information from order flow and market-wide returns more efficiently on days when HFT participation is high.     

Does player specialization predict player actions? Evidence from penalty kicks at FIFA World Cup and UEFA Euro Cup

Penalty kicks are analysed in the literature as ‘real life experiments’ for assessing the use of rational mixed strategies by professional players. However, each penalty kick cannot be considered a repetition of the same event because of the varying background conditions, in particular the heterogeneous ability of different players. Consequently, aggregate statistics over data sets composed of a large number of penalty kicks mediate the behaviour of the players in different games, and the properties of optimal mixed strategies cannot be tested directly because of aggregation bias. In this article, we model the heterogeneous ability of players. We then test the hypothesis that differently talented players randomize over different actions. To achieve this aim, we study a data set that collects penalties kicked during shoot-out series in the last editions of FIFA World Cup and UEFA Euro Cup (1994–2012) where kickers are categorized as specialists and non-specialists. The results support our theoretical predictions.     

Compositional data analysis and zeros in micro data

The application of compositional data analysis methods in economics has some attraction. The methodology relies upon the use of 'log-ratios' in the statistical analysis. Such an approach is not possible when the data to be analysed include observations where the observed budget share is zero. We, therefore, consider and extend the methods of compositional data analysis in the situation where the data to be analysed include observations where the observed budget share is zero. The modified compositional data methods are discussed both in statistical terms and through potential economic interpretations of the method. Further, the modified methodology is applied to the 1988-89 Australian Household Expenditure Survey yielding estimates for a system of Engel curves.     

Common analyst links and predictable returns: Evidence from China

Based on shared analyst coverage, we are the first to document the common-analyst momentum (CAM) effect in China. Empirically, we show that average returns of common-analyst peer firms have strong predictive power for future focal firm returns. Moreover, the CAM effect is stronger than other cross-asset momentum (XAM) effects. Interestingly but differently, the CAM cannot unify other XAM effects as the U.S. market does. Exploiting the underlying mechanism, we find that common-analyst-connected firms are fundamentally similar. Further, the CAM effect is stronger when inter-firm linkages are stronger when the information processing task is more complex and on earnings announcement dates. We conclude that sluggish analyst forecasting and investors’ attention constraint could contribute to the stronger CAM effect, and our results support the hypothesis that slow information diffusion generates the CAM effect.     

中国地区工业绿色全要素生产率增长:——基于方向性距离函数的经验分析

结合方向性距离函数和跨期数据包络分析法,测度绿色全要素生产率增长时尽可能地避免了出现技术倒退结论。中国省份工业的经验分析表明:忽略非期望产出的全要素生产率增长被高估,并混淆了技术进步和技术效率变化的相对贡献;技术无效率普遍存在且省际差异和年际波动性大,但这与经济发展水平无关;绿色全要素生产率变化也存在省际差异和年际波动特点,其中技术进步是其增长的主要源泉,而技术效率恶化是其倒退的根本原因;绿色全要素生产率增长存在明显的倒U型趋势和趋同性,而且外资利用印证了"污染天堂"假说。     

Bond risk premia and realized jump risk

We find that augmenting a regression of excess bond returns on the term structure of forward rates with an estimate of the mean realized jump size almost doubles the R² of the forecasting regression. The return predictability from augmenting with the jump mean easily dominates that offered by augmenting with options-implied volatility and realized volatility from high-frequency data. In out-of-sample forecasting exercises, inclusion of the jump mean can reduce the root mean square prediction error by up to 40%. The incremental return predictability captured by the realized jump mean largely accounts for the countercyclical movements in bond risk premia. This result is consistent with the setting of an incomplete market in which the conditional distribution of excess bond returns is affected by a jump risk factor that does not lie in the span of the term structure of yields.