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The risk/return trade‐off has been a central tenet of portfolio management since the seminal work of Markowitz [1952]. The basic premise, that higher (expected) returns can only be achieved at the expense of greater risk, leads naturally to the concept of an efficient frontier. The efficient frontier defines the maximum return that can be achieved for a given level of risk or, alternatively, the minimum risk that must be incurred to earn a given return. Traditionally, market risk has been measured by the variance (or standard deviation) of portfolio returns, and this measure is now widely used for credit risk management as well. For example, in the popular Credit‐Metrics methodology (J.P. Morgan [1997]), the standard deviation of credit losses is used to compute the marginal risk and risk contribution of an obligor. Kealhofer [1998] also uses standard deviation to measure the marginal risk and, further, discusses the application of mean‐variance optimization to compute efficient portfolios. While this is reasonable when the distribution of gains and losses is normal, variance is an inappropriate measure of risk for the highly skewed, fat‐tailed distributions characteristic of portfolios that incur credit risk. In this case, quantile‐based measures that focus on the tail of the loss distribution more accurately capture the risk of the portfolio. In this article, we construct credit risk efficient frontiers for a portfolio of bonds issued in emerging markets, using not only the variance but also quantile‐based risk measures such as expected shortfall, maximum (percentile) losses, and unexpected (percentile) losses.

This chapter provides a survey of alternative methodologies for measuring and comparing productivity and efficiency of airlines, and reviews representative empirical studies. The survey shows the apparent shift from index procedures and traditional OLS estimation of production and cost functions to stochastic frontier methods and Data Envelopment Analysis (DEA) methods over the past three decades. Most of the airline productivity and efficiency studies over the last decade adopt some variant of DEA methods. Researchers in the 1980s and 1990s were mostly interested in the effects of deregulation and liberalization on airline productivity and efficiency as well as the effects of ownership and governance structure. Since the 2000s, however, studies tend to focus on how business models and management strategies affect the performance of airlines. Environmental efficiency now becomes an important area of airline productivity and efficiency studies, focusing on CO₂ emission as a negative or undesirable output. Despite the fact that quality of service is an important aspect of airline business, limited attempts have been made to incorporate quality of service in productivity and efficiency analysis.

The purpose of this paper is to evaluate the extent of technical efficiency in 27 public sector banks operating in India and to provide strict ranking to these banks.

Two popular data envelopment analysis (DEA) models, namely, CCR model and Andersen and Petersen's super‐efficiency model, were utilized. The cross‐section data for the financial year 2004/2005 were used for obtaining technical efficiency scores.

The results show that only seven of the 27 banks are found to be efficient and thus, defined the efficient frontier; and technical efficiency scores range from 0.632 to 1, with an average of 0.885. Thus, Indian public sector banks, on an average, waste the inputs to the tune of 11.5 percent. Andhra Bank has been observed to be the most efficient bank followed closely by Corporation Bank. Further, the banks affiliated with SBI group turned out to be more efficient than the nationalized banks. The regression results incisively indicate that the exposure to off‐balance sheet activities, staff productivity, market share and size are the major determinants of the technical efficiency.

The practical implication of the research findings is that apart from the proportional reduction of all inputs equivalent to the amount of technical inefficiency, most of the inefficient public sector banks need to reduce the use of the physical capital and augment non‐interest income to project themselves on the efficient frontier.

This paper is the first to provide a strict ranking of Indian public sector banks on the basis of super‐efficiency scores.

Markowitz showed that assets can be combined to produce an “efficient” portfolio that will give the highest level of portfolio return for any level of portfolio risk, as measured by variance or standard deviation. These portfolios can then be connected to generate what is termed an “efficient frontier” (EF). Discusses the calculation of the efficient frontier for combinations of assets, again using the spreadsheet optimizer. To illustrate the derivation of the efficient frontier, uses the data from the Investment Property Databank Long Term Index of Investment Returns for the period 1971 to 1993. Many investors might require a certain specific level of holding or a restriction on holdings in at least some of the assets. Such additional constraints may be readily incorporated into the model to generate a constrained EF with upper and/or lower bounds. This can then be compared with the unconstrained EF to see whether the reduction in return is acceptable. To see the effect that these additional constraints may have, adopts a fairly typical pension fund profile, with no more than 20 per cent of the total held in property. Shows that it is now relatively easy to use the optimizer available in at least one spreadsheet (EXCEL) to calculate efficient portfolios for various levels of risk and return, both constrained and unconstrained, so as to be able to generate any number of efficient frontiers.

In an effort to help policy makers develop competitive postal service strategies, the purpose of this paper is to evaluate the comparative operating efficiencies of postal services across the Organization for Economic Cooperation and Development (OECD) nations and then identify room for service improvement.

As a better alternative to the conventional data envelopment analysis (DEA) which requires the proportional improvements of inputs and outputs simultaneously, the authors propose the combined use of both context-dependent and measure-specific DEAs to measure the relative attractiveness and progress of the national postal operators of OECD countries.

Defying the conventional notion that public enterprises operate less efficiently than private enterprises, the author discovered that some state-owned public enterprises such as postal service operators could still be efficient if managed properly. Even inefficient postal services operators could significantly improve their service performances, once they identified the root causes of their service failures. Through a series of model experiments and testing, the authors found that proposed context-dependent and measure-specific DEA models were more useful for finding such causes than the conventional DEA model.

For public officials and policy makers, the proposed DEAs can pinpoint what it takes to become more efficient and what steps need to be taken to improve postal service operations gradually.

This paper is the first to combine the context-dependent DEA with measure-specific DEA to evaluate the comparative efficiency (or progress) and inefficiency (or regress) of the national postal operators of 25 OECD countries.

The purpose of the research presented in this paper is to evaluate the efficiency and productivity of the European retailers.

Applying a two‐stage approach at individual and global levels, in this study the paper adopts the efficient frontier approach using the Malmquist index, based on DEA to measure productivity of European retailers.

An efficiency and productivity evaluation process is developed incorporating non‐parametric techniques in the European retail sector for the period of 1998‐2006. The author proposes an integrated benchmarking framework illustrated in two stages. In the first stage, work is carried out in an individualized way at the country level identifying the firms that form the corresponding efficient frontier. In a second stage a benchmarking analysis is carried out starting from the selection of the best firms made in the first stage. In this case the firms belonging to different countries are compared against each other. The aim of this procedure is to seek out those best practices that will lead to improved performance throughout the whole sample. The results confirm that convergence/divergence in efficiency and productivity growth do not have the same behaviour patterns, concluding that some countries experienced improvements while others worsened. Individual scrutiny (benchmarks) in the second stage shows that there are four groups of firms that have allowed us to extract important managerial implications.

The paper proposes an integrated benchmarking framework illustrated in two stages. With this methodology answers can be given to important questions such as, how efficient and productive is European retailing? What is the evolution of the productivity over time in Europe? Do different patterns of convergence/divergence of the efficiency exist among the analysed countries? What characteristics do the firms with the best managerial practices belonging to the European global frontier have?

The purpose of this paper is to estimate the performance of 188 mutual funds relative to the risk/return frontier accounting for the transaction costs of producing a portfolio of investments.

The directional output distance function is used to estimate mutual fund performance. The method allows the data to define a frontier of return and risk accounting for the transaction costs associated with securities management and production of risky returns. Proxies for the transaction costs of producing a portfolio of securities include the turnover ratio, load, expense ratio, and net asset value. The estimates of mutual fund performance are bootstrapped to account for the unknown data generating process. By comparing each mutual fund’s performance relative to the capital market line the authors determine how the fund should adjust their portfolio in regard to risk and return in order to maximize the inefficiency adjusted Sharpe ratio.

The bootstrapped estimates indicate that the average mutual fund could simultaneously expand return and contract risk by 3.2 percent if it were to operate on the efficient frontier. After projecting each mutual fund’s return and risk to the efficient frontier the authors find that a majority of the mutual funds should reduce risk to be consistent with the capital market line.

Many researchers have used data envelopment analysis to estimate a piecewise linear frontier of risk and return to measure mutual fund performance. To the authors’ knowledge the research is the first to use a twice-differentiable quadratic directional distance function to measure the managerial performance and risk/return tradeoff of mutual funds.

As cable and satellite industry undergoes transformation in the 21st century with the onslaught of innovation-driven changes, it is important to know which company is doing better and which company is falling behind. This study compares the relative performance of eight cable companies using three factors: operating expense for every dollar of operating revenue, earnings before interest, taxes, depreciation, and amortization, and return on assets. We also evaluate the performance of each firm against itself for the period 2010–2013 to see if they show improvement or deterioration in operating efficiency.

Healthcare industry, the largest sector of the US economy, is going through a dramatic transformation as the US economy recovers out of the current recession. In this chapter, we use data envelopment analysis, an operations research technique, to benchmark the performance of 12 publicly managed care organizations against one another for the period 2009–2011. We find that only 6 companies out of 12 are 100% efficient. We also identify the areas in which inefficient companies are lagging behind their efficient peers.

This paper examines the effect of cryptocurrencies on the portfolio risk-adjusted returns of traditional and alternative investments within an emerging market economy.

The paper employs daily arithmetic returns from August 2015 to October 2018 of traditional assets (stocks, bonds, currencies), alternative assets (commodities, real estate) and cryptocurrencies. Using the mean-variance analysis, the Sharpe ratio, the conditional value-at-risk and the mean-variance spanning tests.

The paper documents evidence to support the diversification benefits of cryptocurrencies by utilising the mean-variance tests, improving the efficient frontier and the risk-adjusted returns of the emerging market economy portfolio of investments.

This paper firmly broadens the Modern Portfolio Theory by authenticating cryptocurrencies as assets with diversification benefits in an emerging market economy investment portfolio.

As far as the authors are concerned, this paper presents the first evidence of the effect of diversification benefits of cryptocurrencies on emerging market asset portfolios constructed using traditional and alternative assets.