Non-smooth optimization methods for computation of the conditional value-at-risk and portfolio optimization

We examine numerical performance of various methods of calculation of the Conditional Value-at-risk (CVaR), and portfolio optimization with respect to this risk measure. We concentrate on the method proposed by Rockafellar and Uryasev in (Rockafellar, R.T. and Uryasev, S., 2000, Optimization of conditional value-at-risk. Journal of Risk, 2, 21-41), which converts this problem to that of convex optimization. We compare the use of linear programming techniques against a non-smooth optimization method of the discrete gradient, and establish the supremacy of the latter. We show that non-smooth optimization can be used efficiently for large portfolio optimization, and also examine parallel execution of this method on computer clusters.

A survey of value-at-risk and its role in the banking industry

This paper discusses the various aspects of Value-at-Risk (VaR) and the VaR-based risk management process as it pertains to the banking industry. Since its inception in the 1990’s, VaR has become the industry standard by which market risk is both measured and managed by financial institutions today. However, there has been much debate regarding VaR’s validity and the extent of its role within the banking industry. Yet, now that it is an integral part of the regulatory framework, establishing VaR’s legitimacy is more important than ever. Therefore, this paper examines the recent literature on VaR’s use as a market risk management tool within the banking environment in an attempt to clarify some of the more contentious issues which have been raised by researchers. The discussion begins by highlighting the underlying theory on which VaR is based, specific aspects which have proven controversial and its use from a regulatory perspective. The focus then turns to what little literature exists on the subject of VaR and asset returns in an attempt to provide some direction for future research.

On the determinants of derivative usage by Australian companies

This paper provides an examination of the determinants of derivative use by Australian corporations. We analysed the characteristics of a sample of 469 firm/year observations drawn from the largest Australian publicly listed companies in 1999 and 2000 to address two issues: the decision to use financial derivatives and the extent to which they are used. Logit analysis suggests that a firm's leverage (distress proxy), size (financial distress and setup costs) and liquidity (financial constraints proxy) are important factors associated with the decision to use derivatives. These findings support the financial distress hypothesis while the evidence on the underinvestment hypothesis is mixed. Additionally, setup costs appear to be important, as larger firms are more likely to use derivatives. Tobit results, on the other hand, show that once the decision to use derivatives has been made, a firm uses more derivatives as its leverage increases and as it pays out more dividends (hedging substitute proxy). The overall results indicate that Australian companies use derivatives with a view to enhancing the firms' value rather than to maximizing managerial wealth. In particular, corporations' derivative policies are mostly concerned with reducing the expected cost of financial distress and managing cash flows. Our inability to identify managerial influences behind the derivative decision suggests a competitive Australian managerial labor market.

Low-frequency volatility of yen interest rate swap market in relation to macroeconomic risk

Using ‘low-frequency’ volatility extracted from aggregate volatility shocks in interest rate swap (hereafter, IRS) market, this paper investigates whether Japanese yen IRS volatility can be explained by macroeconomic risks. The analysis suggests that this low-frequency yen IRS volatility has strong and positive association with most of the macroeconomic risk proxies (e.g., volatility of consumer price index, industrial production volatility, foreign exchange volatility, slope of the term structure and money supply) with the exception of the unemployment rate, which is negatively related to IRS volatility. This finding is fairly consistent with the argument that the greater the macroeconomic risk the greater is the use of derivative instruments to hedge or speculate. The relationship between the macroeconomic risks and IRS volatility varies slightly across the different swap maturities but is robust to alternative volatility specifications. This linkage between swap market and macroeconomy has practical implications since market makers and hedgers use the swap rate as benchmark for pricing long-term interest rates, corporate bonds and various other securities.

Selection of the right risk measures for portfolio allocation

 An optimisation framework is proposed to enable investors to select the right risk measures in portfolio selection. Verification is deployed by performing experiments in developed markets (e.g., the US stock market), emerging markets (e.g., the South Korean stock market) and global investments. A preselection procedure dealing with large datasets is also introduced to eliminate stocks that have low diversification potential before running the portfolio optimisation model. Portfolios are evaluated by four performance indices, i.e., the Sortino ratio, the Sharpe ratio, the Stutzer performance index, and the Omega measure. Experimental results demonstrate that high performance and also well-diversified portfolios are obtained if modified value-at-risk, variance, or semi-variance is concerned whereas emphasising only skewness, kurtosis or higher moments in general produces low performance and poorly diversified portfolios. In addition, the preselection applied to large datasets results in portfolios that have not only high performance but also high diversification degree.

Fuzzy portfolio allocation models through a new risk measure and fuzzy sharpe ratio

A new portfolio risk measure that is the uncertainty of portfolio fuzzy return is introduced in this paper. Beyond the well-known Sharpe ratio (i.e., the reward-to-variability ratio) in modern portfolio theory, we initiate the so-called fuzzy Sharpe ratio in the fuzzy modeling context. In addition to the introduction of the new risk measure, we also put forward the reward-to-uncertainty ratio to assess the portfolio performance in fuzzy modeling. Corresponding to two approaches based on TM and TW fuzzy arithmetic, two portfolio optimization models are formulated in which the uncertainty of portfolio fuzzy returns is minimized, while the fuzzy Sharpe ratio is maximized. These models are solved by the fuzzy approach or by the genetic algorithm (GA). Solutions of the two proposed models are shown to be dominant in terms of portfolio return uncertainty compared with those of the conventional mean-variance optimization (MVO) model used prevalently in the financial literature. In terms of portfolio performance evaluated by the fuzzy Sharpe ratio and the reward-to-uncertainty ratio, the model using TW fuzzy arithmetic results in higher performance portfolios than those obtained by both the MVO and the fuzzy model, which employs TM fuzzy arithmetic. We also find that using the fuzzy approach for solving multiobjective problems appears to achieve more optimal solutions than using GA, although GA can offer a series of well-diversified portfolio solutions diagrammed in a Pareto frontier.

Non-homogeneous volatility correlations in the bivariate multifractal model

In this paper, we consider an extension of the recently proposed bivariate Markov-switching multifractal model of Calvet, Fisher, and Thompson [2006. "Volatility Comovement: A Multifrequency Approach." Journal of Econometrics {131}: 179-215]. In particular, we allow correlations between volatility components to be non-homogeneous with two different parameters governing the volatility correlations at high and low frequencies. Specification tests confirm the added explanatory value of this specification. In order to explore its practical performance, we apply the model for computing value-at-risk statistics for different classes of financial assets and compare the results with the baseline, homogeneous bivariate multifractal model and the bivariate DCC-GARCH of Engle [2002. "Dynamic Conditional Correlation: A Simple Class of Multivariate Generalized Autoregressive Conditional Heteroskedasticity Models." Journal of Business & Economic Statistics 20 (3): 339-350]. As it turns out, the multifractal model with heterogeneous volatility correlations provides more reliable results than both the homogeneous benchmark and the DCC-GARCH model. © 2014 Taylor & Francis.

Islamic or conventional mutual funds: who has the upper hand? Evidence from Malaysia

Contradictory results are documented in the literature regarding which type of mutual fund has superior performance; an Islamic or conventional mutual fund. Due to the relative short history of the Islamic mutual funds' industry, prior literature has inevitably relied on a small sample size with a short sample period. With the longest applicable sample period, this study represents one of the most recent attempts to address this conflicting evidence. We find there is no clear cut over performance by Islamic mutual funds against their conventional peers across the three financial crises in our sample period, with the exception of the most recent global financial crisis, where Islamic mutual funds generally outperformed their conventional counterparts. We further find that Islamic funds significantly outperformed conventional funds in the riskiest asset class, equity, one year before and during the global financial crisis. We further reveal that the modified value at risk for Islamic mutual funds was significantly lower than their conventional peers during the global financial crisis. This seems to indicate that Islamic mutual funds have better risk management compared to conventional peers.

An Analysis of the Association Between Firm Risk, Executive Share Options and Accounting Performance: Some Australian Evidence

This paper examines whether the financial performance of the firm is associated with the risk-taking propensity of executives, which is inferred from the structure of their share option portfolio. The objective of this paper is to determine if executives have greater risk bearing preferences when they have more share options than shares in their firm. In turn, executives' risk-taking preferences suggest that these decision-makers adopt value-increasing strategies. The results of this study support this notion. The results of the study of 182 Australian firms demonstrate that the negative relationship between firm risk and firm performance is weaker when executives hold a higher proportion of share options than shares in their investment in the firm. These results hold implications for executives' compensation contracts. That is, executives who share in their firms' risk via share options are more likely to undertake risky activities with high-expected performance outcome.

Risk allocation in public-private partnership projects

Both the increasing private participation in public projects and the critical importance of appropriate risk allocation to the success of public-private partnership (PPP) projects justify specific research on the risk allocation practice in PPP projects, particularly whether the practice is value-for-money driven. In this paper, the risk allocation in construction projects is examined firstly. The risks associated with PPP projects and the concept of optimal risk allocation are then reviewed. More importantly, the risk allocation practice in PPP projects is examined, particularly in the Australian context. Important issues, such as the current practice, the governments' accountability, and achieving efficient allocation, are discussed. The discussion presented in this paper is expected to justify and elicit further research on how to achieve efficient risk allocation in PPP projects

Assessment of fracture risk : value of random population-based samples - the Geelong Osteoporosis Study

Fracture risk is determined by bone mineral density (BMD). The T-score, a measure of fracture risk, is the position of an individual's BMD in relation to a reference range. The aim of this study was to determine the magnitude of change in the T-score when different sampling techniques were used to produce the reference range. Reference ranges were derived from three samples, drawn from the same region: (1) an age-stratified population-based random sample, (2) unselected volunteers, and (3) a selected healthy subset of the population-based sample with no diseases or drugs known to affect bone. T-scores were calculated using the three reference ranges for a cohort of women who had sustained a fracture and as a group had a low mean BMD (ages 35-72 yr; n = 484). For most comparisons, the T-scores for the fracture cohort were more negative using the population reference range. The difference in T-scores reached 1.0 SD. The proportion of the fracture cohort classified as having osteoporosis at the spine was 26, 14, and 23% when the population, volunteer, and healthy reference ranges were applied, respectively. The use of inappropriate reference ranges results in substantial changes to T-scores and may lead to inappropriate management.

Value-added role of internal audit : an Ethiopian case study

Purpose – The purpose of this paper is to draw inferences – from the results of an Ethiopian public sector corporation (for-profit) case study – on how the attributes of a value-adding internal audit department would vary among organisations.

Design/methodology/approach – The case study strategy is employed. The internal audit function of a public sector corporation was examined using an analytical framework derived from the literature. Research evidence was gathered distributing questionnaires to managers and internal auditors, conducting a semi-structured interview with the internal audit department manager, and reviewing documents.

Findings – The results highlight that traditional/compliance audit is dominant in the organisation studied as contrasted with value-added auditing. The paper concludes that goals and strategies pursued and the level of risk faced by organisations to which internal audit provides service, appear to shape the attributes of a value-adding internal audit department. The study also demonstrates that the quality of strategic planning for, and marketing of, internal audit would influence the extent to which an appropriate value-added profile is attained in a particular context.

Research limitations/implications – Since a single unit of analysis is examined, universal generalisability of the findings cannot be claimed. Also, the research design assumed that the unit of analysis investigated falls within the scope of internal audit departments considered in the literature that served as a basis to develop the analytical framework and data collection instruments.

Originality/value – The paper is expected to inspire conclusive follow-on research on the role of internal audit in Ethiopia, or other countries with similar settings.

Societal role expectations of management accounting professionals: an Australian study

Purpose This paper seeks to advance the understanding of the relevance of management accounting (MA) as a profession by examining societal role expectations of MA professionals in Australia.Methodology/approach The study presented in this paper is based on a questionnaire survey.Findings Findings of the study show that Australian MA professionals are expected to have skills in cost management, corporate social responsibility, carbon accounting, risk management, business analysis, corporate governance, and asset valuations. The demand of MA professionals exceeded the pool of MA talents in Australia. The role expectations of MA professionals from different stakeholder groups are fairly consistent.Social implications The study adds to the immigration institution discussion by demonstrating that there are inadequate professionals in Australia with the skills and experience in MA to meet the projected demand. Australia has very little option but to fill the supply-side shortfall in the short-term with overseas MA professionals.Originality/value The study adds to the literature of the societal relevance of MA by providing evidence of an increasing demand for MA skills in Australia.

The value of work in younger and older adults' lives: an Australian perspective

In the present study we examined the perceived role of work in the lives of younger and older adults in three different occupations: teaching, nursing, and small business. On the basis of lifespan developmental theory of changes in work-related values across the lifespan we expected that (1) older adults would rate their job satisfaction and organisational commitment more highly than younger adults, and (2) younger adults would rate the importance of work more highly than older workers. Based on utility theory we expected that nurses and teachers would view early retirement more positively than small business employees because of early retirement incentives in these two careers. One-hundred-sixty-two participants completed a 118-item survey. Overall few age differences were found between older and younger workers. On average, all participants rated work as moderately important and their job satisfaction as moderately high. Nonetheless, older participants rated their job satisfaction higher than younger participants. On average, all groups believed they would retire before 65 years of age. The latter finding is important for workability theory and raises issues about how to change attitudes, perceptions and values about working past traditional retirement ages.