Optimizing tracking error-constrained portfolios

Active portfolios subject to tracking error (TE) constraints are the typical setup for active managers tasked with outperforming a benchmark. The risk and return relationship of such constrained portfolios is described by an ellipse in traditional mean-variance space and the ellipse’s flat shape suggests an additional constraint which improves the performance of the active portfolio. Although subsequent work isolated and explored different portfolios subject to these constraints, absolute portfolio risk has been consistently ignored. A different restriction – maximization of the traditional Sharpe ratio on the constant TE frontier in absolute risk/return space – is added here to the existing constraint set, and a method to generate this portfolio is explained. The resultant portfolio has a lower volatility and higher return than the benchmark, it satisfies the TE constraint and the ratio of excess absolute return to risk is maximized (i.e. maximum Sharpe ratio in absolute space).     

Efficiency of hospitals in Germany: a DEA-bootstrap approach

Various attempts to assess the performance of German hospitals have generated a wide range of estimates regarding their efficiency. These attempts were based on different, often rather small data sets consisting of heterogeneous hospitals; the techniques applied range from simple benchmarking approaches to studies which employ Data Envelopment Analysis (DEA). Some studies report ‘dramatic differences in efficiency’ and propose savings potentials of 50%; others find an average efficiency in excess of 95% and characterize almost 75% of their observations as fully efficient. This study presents results for two datasets representative of two segments of the German hospital system. These segments comprise all hospitals that have one internal medicine and one surgery department; the hospitals are located in the old federal states of Germany. None of the hospitals provides tertiary care. DEA can be applied because all hospitals offer a comparable quality and range of services. The results were estimated with a DEA-bootstrapping procedure and suggest an average bias–corrected efficiency of around 80%.     

Competition and efficiency in the MENA banking region: a non-structural DEA approach

The goal of this article is to empirically assess the relationship between competition and efficiency in the banking sector of Middle East and North African (MENA) countries spanning the period 1997–2011. To measure the level of competition, the article estimates the non-structural indicator known as the H-statistic, while the level of bank efficiency is estimated through the nonparametric methodology of the Data Envelopment Analysis (DEA) and the Bootstrap Data Envelopment Analysis (BDEA), respectively. The empirical results are robust under six econometric methodologies, providing sufficient evidence for the presence of a one-way (negative) Granger causality, running from efficiency to competition. The empirical findings lead to the rejection of the ‘Efficient Structure Hypothesis’, implying that increases in competition do not precede increases in cost efficiency.     

Retail‐bank efficiency: Nonstandard goals and environmental determinants

This paper analyzes technical and scale efficiency of Austrian savings and cooperative banks. Non‐profit objectives are also considered with respect to input–output choice, which contributes to adequate performance measurements for alternative banks. Efficiency score estimates obtained via Data Envelopment Analysis (DEA) reveal considerable potential for improvement in terms of intermediation efficiency. Several environmental determinants prove significant, but the cumulative predictive content of exogenous factors is rather modest. Bank efficiency improves in both underdeveloped and prosperous markets, while increased rival size and distance appear to be detriments to efficiency. A concluding discussion of confounding factors reveals the managerial, stakeholder, and policy implications of the results.     

Testing commodity futures market efficiency under time-varying risk premiums and heteroscedastic prices

We propose a novel test to measure market efficiency while estimating the time-varying risk premiums of commodity futures, given that the prices are heteroscedastic. The risk premium is estimated using a state-space model with a Kalman filter modified for heteroscedasticity. Using 79 commodity futures traded on 16 exchanges during the period 2000–2014 and a Monte Carlo simulation, we demonstrate that the proposal produces robust results compared with conventional approaches. The global financial crisis has improved the efficiency and affected the trading volumes of commodity futures, but it has had no effect on the average or the volatility of risk premiums.     

DO LABOUR SOCIETIES PERFORM DIFFERENTLY TO COOPERATIVES? EVIDENCE FROM THE SPANISH BUILDING INDUSTRY

ABSTRACT: Labour Societies and Cooperatives are both Social Economy enterprises, but with noticeable differences, some of which are imposed by legislation in Spain. The aim of this paper is to study whether such differences affect their management capacity and, in particular, efficiency. In doing so, Data Envelopment Analysis techniques and the metafrontier approach proposed by O’Donnell et al. (2008) are used on a sample of Spanish Labour Societies and Cooperatives belonging to the building industry. Scores of technical efficiency and metafrontier ratios are computed at firm level and, as a novel contribution to existing literature in this field of research, at input‐specific level. The main finding shows that Cooperatives enjoy some technological advantages over Labour Societies, particularly in regard to the management of labour, fixed assets and current assets.     

动量思想与大宗商品的战术配置价值*——基于Black Litterman模型

本文讨论了大宗商品的战术资产配置价值。通过利用1973—2016年的季度数据，笔者提出了基于动量思想的Black Litterman配置模型。该配置模型表明，在传统股票债券组合中加入GSCI大宗商品指数会明显改善组合的回报。在适当的策略周期下，加入大宗商品指数还能够提高组合的夏普比。这表明，大宗商品指数的战术配置价值明显。与其他常见的配置模型相比，本文提出的基于动量思想的Black Litterman模型表现相对较好。上述发现在经过交易成本调整后仍然成立。     

Banking Sector Performance in Latin America: Market Power versus Efficiency

Since the mid‐1990s the banking sector in the Latin American emerging markets has experienced profound changes due to financial liberalization, a significant increase in foreign investments, and greater merger activities often occurring following financial crises. The wave of consolidation and the rapid increase in market concentration that took place in most countries has generated concerns about the rise in banks' market power and its potential effects on consumers. This paper advances the existing literature by testing the market power (Structure–Conduct–Performance and Relative Market Power) and efficient structure (X‐ and scale efficiency) hypotheses for a sample of over 2500 bank observations in nine Latin American countries over 1997–2005. We use the Data Envelopment Analysis technique to obtain reliable efficiency measures. We produce evidence supporting the efficient structure hypotheses. The findings are particularly robust for the largest banking markets in the region, namely Brazil, Argentina, and Chile. Finally, capital ratios and bank size seem to be among the most important factors in explaining higher than normal profits for Latin American banks.     

Non-linear dependence modelling with bivariate copulas: statistical arbitrage pairs trading on the S&P 100

We develop a copula-based pairs trading framework and apply it to the S&P 100 index constituents from 1990 to 2014. We propose an integrated approach, relying on copulas for pairs selection and trading. Essentially, we fit t-copulas to all possible combinations of pairs in a formation period. Next, we trade these pairs in-sample to assess the profitability of mispricing signals derived from t-copulas. The top pairs are transferred to an out-of-sample trading period, and traded with individualized exit thresholds. In particular, we differentiate between pairs exhibiting mean-reversion and momentum effects and apply idiosyncratic take-profit and stop-loss rules. For the top 5 mean-reversion pairs, we find out-of-sample returns of 7.98% per year; the top 5 momentum pairs yield 7.22% per year. Standard deviations are low, leading to annualized Sharpe ratios of 1.52 (top 5 mean-reversion) and 1.33 (top 5 momentum), respectively.     

On the Use of the Moving Average Trading Rule to Test for Weak Form Efficiency in Capital Markets

The examination for the possible existence of predictive power in the moving average trading rule has been used extensively to test the hypothesis of weak form market efficiency in capital markets. This work focuses mainly on the study of the variation of the moving average (MA) trading rule performance as a function of the length of the longer MA. Empirical analysis of daily data from NYSE and the Athens Stock Exchange reveal high variability of the performance of the MA trading rule as a function of the MA length and on some occasions the series of successive trading rule total returns is non‐stationary. These findings have direct implications in weak form market efficiency testing. Indeed, given this high variability of the performance of the MA trading rule, by just finding out that trading rules with some specific combinations of MA lengths can or cannot beat the market, as is the case in most of the published work thus far, is not enough evidence for or against the existence of weak form market efficiency. Results also show that on average in about three out of four cases trading rule signals are false, a fact that leaves a lot of space for improved trading rule performance if trading rule signals are combined with other information (e.g. filters, or volume of trade). Finally, some evidence of enhanced trading rule performance for the shorter MA lengths was found. This enhanced performance is partly attributed to the higher probability that a trading rule signal is not a whipsaw, as well as to the larger number of days out‐of‐the‐market which are associated with shorter MA lengths.     

Modelling the effect of national culture on countries’ innovation performances: A conditional full frontier approach

This paper provides empirical evidence of the link between countries’ cultural factors and innovation performance. By defining innovation process in a knowledge production framework it uses conditional and unconditional Data Envelopment Analysis (DEA) models together with data from the European Innovation Scoreboard for the year 2007 and Hofstede’s cultural indexes. In this way it models and measures the effect of cultural values on 25 European countries’ innovation efficiency levels. The empirical results reveal that national culture can impact countries’ innovation performance. Specifically, we find significant negative effects on countries’ innovation efficiency levels for countries with higher power distance and uncertainty avoidance values.     

Efficiency of Junior High Schools and the Role of Proprietary Structure

Abstract: In this paper we deal with the role of proprietary structure in explaining efficiency within the Italian school industry. We analyze a sample of 497 schools located in Piemonte, a region in the North‐Western part of the country, distinguishing between public, private for‐profit and private nonprofit schools. In stage one of the analysis, we provide robust estimates of efficiency scores, using the two most widely known techniques in applied works, namely Data Envelopment Analysis (DEA) and Stochastic Frontiers (SF). In stage two, we suggests that proprietary structure matters in explaining efficiency. Nonprofit schools are more efficient than public ones, whereas for‐profit counterparts are outperformed by public producers. Moreover, we find that foreign and disabled students affects negatively efficiency, raising concerns for cream‐skimming practices among private producers. Finally, school size is another important determinant of efficiency.     

基于DEA模型的中国客车类上市公司经营绩效评估

入世后,我国客车类上市公司面临着严峻的竞争压力,迫使客车类上市公司不断提高其竞争力。笔者在数据包络分析的C2R和C2GS2模型基础上,建立了一种客车类上市公司经营绩效评价和排序的数学模型,对我国客车类上市公司的相对经营绩效进行实证分析,以弥补常规指标比较的不足。最后,本文提出了经营绩效差的客车类上市公司改善其经营绩效的有效措施。     

Productivity and efficiency change and shareholder value: evidence from the Spanish banking sector

Productivity change and shareholder value have been analysed in the banking sector in the last few years, although it should be noted that these two important aspects have been studied separately. In this regard, the main contribution of our study is to link these two lines of research by verifying whether those banks characterized by higher levels of efficiency and productivity change have a higher shareholder value. To measure changes in efficiency and productivity we use the Malmquist nonparametric technique, which is calculated from Data Envelopment Analysis (DEA) linear programming approach. The Malmquist total factor productivity index enables separation of the ‘catching up’ effect, i.e. changes over time in technical efficiency, from ‘technological change’, i.e. the shift of best practice frontier over time due to technological progress. Our results for a sample of listed Spanish banks in the period 2000 to 2004 confirm that those banks with higher efficiency and productivity changes have a higher shareholder value, even after controlling for the impact of traditional measures of performance, such as return on assets.     

Performance des activités d'éducation et de recherche des systèmes d'enseignement supérieur de l'OCDE

Most of the studies in the literature on performance in higher education focus on international comparisons of education expenditure, mainly the expenditure per student, and do not take into account the multi-dimensional outcome of higher education activities, i.e. research and education. To go thoroughly into the analysis of higher education systems performance, we develop a complementary approach based on the notion of efficiency ("Data Envelopment Analysis" method). Moreover, we evaluate the internal and external efficiency of education and research activities performed by higher education systems, by taking into consideration the labour market integration of the graduates and the publications weighted by the number of researchers. Taking into account the two-dimensional activity of higher education and introducing qualitative measures of education and research outputs strongly modify the level of efficiency of OECD countries compared with a quantitative one-dimensional assessment of higher education performance.
Les éudes de comparaison internationale en matière d'évaluation de l'enseignement supérieur se limitent à une analyse budgétaire bivariée. Dans cet article, nous analysons la performance de l'enseignement supérieur en tenant compte de l'éducation et de la recherche. Cette approche se concentre sur la notion d'efficacité(méthode "Data Envelopment Analysis"). Nous mesurons l'efficacité interne et externe de l'enseignement et de la recherche en tenant compte de l'insertion des diplômés sur le marché du travail et des publications pondérées par le nombre de chercheurs. L'introduction du caractère multi-outputs de l'enseignement supérieur et/ou des mesures qualitatives modifie considérablement le niveau d'efficacitédes pays de l'OCDE.     

中国外资财险企业市场竞争力问题研究

为衡量入世后在中国的外资财险企业的竞争力情况,本文借鉴经典产业组织理论的SCP范式和数据包络分析方法,运用2004-2011年的相关数据,以中国财险业市场结构和生产效率的变化情况为基础,总结其他学者参数设计的利弊,经实证研究发现当前中国财险业市场结构正由寡头垄断型向垄断竞争型优化；财险业尽管实现了全要素生产率连年净增长,但该指标的变化趋势是向下的,而外资公司整体上无论是追赶效应还是前沿面移动效应都优于中资公司,中资仅剩下规模上先占的相对优势.     

Financial liberalization and bank efficiency: a comparative analysis of India and Pakistan

This paper provides a comparative analysis of the evolution of the technical efficiency of commercial banks in India and Pakistan during 1988–1998, a period characterized by far-reaching changes in the banking industry brought about by financial liberalization. Data Envelopment Analysis is applied to two alternative input–output specifications to measure technical efficiency, and to decompose technical efficiency into its two components, pure technical efficiency and scale efficiency. The consistency of the estimated efficiency scores are checked by examining their relationship with three traditional non-frontier measures of bank performance. In addition, the relationship between bank size and technical efficiency is examined. It is found that the overall technical efficiency of the banking industry of both countries improved gradually over the years, especially after 1995. Unlike public sector banks in India, public sector banks in Pakistan witnessed improvement in scale efficiency only. It is also found that banks are relatively more efficient in generating earning assets than in generating income. This is attributed to the presence of high non-performing loans. In addition, it is found that the gap between the pure technical efficiency of different size groups has declined over the years.     

中国烟草加工企业技术效率分析——基于参数方法与非参数方法的对比研究

针对中国烟草加工企业因规模扩张而出现的管理效率低下等问题,使用2000--2006年企业层面的截面数据,运用参数方法和非参数方法测算了中国烟草加工企业的技术效率,并对两种方法的测算结果进行了比较分析。结果表明：两种测算结果存在较高的相关性,测算结果比较可靠;2000--2006年中国烟草加工企业的平均技术效率为0．74～0．79,具有稳步上升趋势;行业整体规模效率较高,但规模报酬递减的企业所占的比重有所增大。     

Evaluation of the green technology innovation efficiency of China's manufacturing industries: DEA window analysis with ideal window width

Data Envelopment Analysis (DEA) window analysis with ideal window width is applied to evaluate the green technology innovation efficiency of 28 manufacturing industries in China during 2006–2014. The obtained results are compared with those calculated using the traditional DEA model, and convergence analysis of the efficiency is conducted. Five years is the obtained ideal window width and DEA window analysis with ideal window produces results closer to reality for China's manufacturing industry. The overall efficiency of the green technology innovation in the manufacturing sector is low following a wave-shaped curve – first decreasing, then increasing and decreasing again, with large inter-industrial differences. There are 8 high-, 14 medium- and 6 low-efficiency industries. A convergence trend in the green technology innovation efficiency within the 28 manufacturing industries exists, implying a catch-up effect between them.     

Estimating the efficiency of general practitioners controlling for case mix and outlier effects

Data on some 600 general practitioners located in the same region of Austria for the years 2001–2003 are analyzed using Data Envelopment Analysis. The available information comprises patient numbers by age category, case mix, and resource use; outliers are removed with a procedure based on the order-m estimator. The results do not vary much over different samples and specifications and imply an average inefficiency of around 15%. Throughout the observation period, only slight changes in total factor productivity are observed.