Are college education and job experience complements or substitutes? Evidence from hedge fund portfolio performance

Review of Quantitative Finance and Accounting - We examine, for various educational characteristics of hedge fund managers, the performance profile of hedge fund portfolios along their...     

Multi-asset portfolio optimization and out-of-sample performance: an evaluation of Black–Litterman,mean-variance,and naïve diversification approaches

The Black–Litterman model aims to enhance asset allocation decisions by overcoming the problems of mean-variance portfolio optimization. We propose a sample-based version of the Black–Litterman model and implement it on a multi-asset portfolio consisting of global stocks, bonds, and commodity indices, covering the period from January 1993 to December 2011. We test its out-of-sample performance relative to other asset allocation models and find that Black–Litterman optimized portfolios significantly outperform naïve-diversified portfolios (1/N rule and strategic weights), and consistently perform better than mean-variance, Bayes–Stein, and minimum-variance strategies in terms of out-of-sample Sharpe ratios, even after controlling for different levels of risk aversion, investment constraints, and transaction costs. The BL model generates portfolios with lower risk, less extreme asset allocations, and higher diversification across asset classes. Sensitivity analyses indicate that these advantages are due to more stable mixed return estimates that incorporate the reliability of return predictions, smaller estimation errors, and lower turnover.     

Which demands affect optimal international portfolio choices?

This study analyzes the asset allocations of simple international portfolios that include domestic risky assets, foreign risky assets, and domestic risk-free bonds, through a theoretical analysis. A close-form solution for the optimal holding rates is derived, and can be further sub-divided into three categories of demand: speculative demand, diversified demand, and hedging demands. We carefully explore the essential problem of identifying the underlying reasons for asset allocations, which in turn allows us to answer the question of which of these demands are critical in influencing holding changes.     

When can you immunize a bond portfolio?

This paper presents a condition equivalent to the existence of a Riskless Shadow Asset that guarantees a minimum return when the asset prices are convex functions of interest rates or other state variables. We apply this lemma to immunize default-free and option-free coupon bonds and reach three main conclusions. First, we give a solution to an old puzzle: why do simple duration matching portfolios work well in empirical studies of immunization even though they are derived in a model inconsistent with equilibrium and shifts on the term structure of interest rates are not parallel, as assumed? Second, we establish a clear distinction between the concepts of immunized and maxmin portfolios. Third, we develop a framework that includes the main results of this literature as special cases. Next, we present a new strategy of immunization that consists in matching duration and minimizing a new linear dispersion measure of immunization risk.     

When do jumps matter for portfolio optimization?

We consider the continuous-time portfolio optimization problem of an investor with constant relative risk aversion who maximizes expected utility of terminal wealth. The risky asset follows a jump-diffusion model with a diffusion state variable. We propose an approximation method that replaces the jumps by a diffusion and solve the resulting problem analytically. Furthermore, we provide explicit bounds on the true optimal strategy and the relative wealth equivalent loss that do not rely on quantities known only in the true model. We apply our method to a calibrated affine model. Our findings are threefold: Jumps matter more, i.e. our approximation is less accurate, if (i) the expected jump size or (ii) the jump intensity is large. Fixing the average impact of jumps, we find that (iii) rare, but severe jumps matter more than frequent, but small jumps.     

Tukey’s transformational ladder for portfolio management

Over the past half-century, the empirical finance community has produced vast literature on the advantages of the equally weighted Standard and Poor (S&P 500) portfolio as well as the often overlooked disadvantages of the market capitalization weighted S&P 500’s portfolio (see Bloomfield et al. in J Financ Econ 5:201–218, 1977; DeMiguel et al. in Rev Financ Stud 22(5):1915–1953, 2009; Jacobs et al. in J Financ Mark 19:62–85, 2014; Treynor in Financ Anal J 61(5):65–69, 2005). However, portfolio allocation based on Tukey’s transformational ladder has, rather surprisingly, remained absent from the literature. In this work, we consider the S&P 500 portfolio over the 1958–2015 time horizon weighted by Tukey’s transformational ladder (Tukey in Exploratory data analysis, Addison-Wesley, Boston, 1977): \(1/x^2,\,\, 1/x,\,\, 1/\sqrt{x},\,\, \text {log}(x),\,\, \sqrt{x},\,\, x,\,\, \text {and} \,\, x^2\), where x is defined as the market capitalization weighted S&P 500 portfolio. Accounting for dividends and transaction fees, we find that the 1/\(x^2\) weighting strategy produces cumulative returns that significantly dominate all other portfolio returns, achieving a compound annual growth rate of 18% over the 1958–2015 horizon. Our story is furthered by a startling phenomenon: both the cumulative and annual returns of the \(1/x^2\) weighting strategy are superior to those of the 1 / x weighting strategy, which are in turn superior to those of the \(1/\sqrt{x}\) weighted portfolio, and so forth, ending with the \(x^2\) transformation, whose cumulative returns are the lowest of the seven transformations of Tukey’s transformational ladder. The order of cumulative returns precisely follows that of Tukey’s transformational ladder. To the best of our knowledge, we are the first to discover this phenomenon.     

Do students’ perceptions matter? A study of the effect of students’ perceptions on academic performance

Prior accounting education literature documents that students typically associate accounting subjects with negative perceptions, but there are also recent suggestions that the stereotype of the accountant has positive associations. These perceptions of accounting are likely to affect students’ attitudes towards learning and, consequently, influence their performance. We examine the relationship between students’ perceptions and students’ performance. The present study involved undergraduate and graduate students enrolled in management accounting subjects. Our findings indicate that students’ performance is negatively affected by the negative perceptions of accounting that students bring to the subject. Our findings also suggest that positive perceptions of accounting held by students at the end of the semester have a positive impact on students’ performance.     

On optimal portfolio diversification with respect to extreme risks

Extreme losses of portfolios with heavy-tailed components are studied in the framework of multivariate regular variation. Asymptotic distributions of extreme portfolio losses are characterized by a functional γ _ξ =γ _ξ (α,Ψ) of the tail index α, the spectral measure Ψ, and the vector ξ of portfolio weights. Existence, uniqueness, and location of the optimal portfolio are analysed and applied to the minimization of risk measures. It is shown that diversification effects are positive for α>1 and negative for α<1. Strong consistency and asymptotic normality are established for a semiparametric estimator of the mapping ξ ↦ γ _ξ . Strong consistency is also established for the estimated optimal portfolio.     

Health status and portfolio choice: Causality or heterogeneity?

This paper explores the role of unobserved individual characteristics in the health-assets and health-portfolio correlations. We apply various econometrics models to a unique longitudinal dataset with rich information that allows for the exploitation of four different health indices. Our findings show strong cross-sectional correlations between health and both financial and non-financial assets, but these correlations seem to be mainly driven by heterogeneity as the correlations largely disappear in the fixed-effects model. Adverse health shocks, however, are found to motivate a safer portfolio choice even after individual fixed-effects are controlled for – a result consistent with the prediction made by the background risk theory. Our findings suggest that health shocks shift investment from risky assets toward other financial assets, but keep the total financial assets unchanged.     

Can you get what you pay for? Pay‐for‐performance and the quality of healthcare providers

Despite the popularity of pay-for-performance (P4P) among health policymakers and private insurers as a tool for improving quality of care, there is little empirical basis for its effectiveness. We use data from published performance reports of physician medical groups contracting with a large network HMO to compare clinical quality before and after the implementation of P4P, relative to a control group. We consider the effect of P4P on both rewarded and unrewarded dimensions of quality. In the end, we fail to find evidence that a large P4P initiative either resulted in major improvement in quality or notable disruption in care.     

Is stochastic volatility relevant for dynamic portfolio choice under ambiguity?

Literature on dynamic portfolio choice has been finding that volatility risk has low impact on portfolio choice. For example, using long-run US data, Chacko and Viceira [2005. “Dynamic Consumption and Portfolio Choice with Stochastic Volatility in Incomplete Markets.” The Review of Financial Studies 18 (4): 1369–1402] found that intertemporal hedging demand (required by investors for protection against adverse changes in volatility) is empirically small even for highly risk-averse investors. We want to assess if this continues to be true in the presence of ambiguity. Adopting robust control and perturbation theory techniques, we study the problem of a long-horizon investor with recursive preferences that faces ambiguity about the stochastic processes that generate the investment opportunity set. We find that ambiguity impacts portfolio choice, with the relevant channel being the return process. Ambiguity about the volatility process is only relevant if, through a specific correlation structure, it also induces ambiguity about the return process. Using the same long-run US data, we find that ambiguity about the return process may be empirically relevant, much more than ambiguity about the volatility process. Anyway, intertemporal hedging demand is still very low: investors are essentially focused on the short-term risk–return characteristics of the risky asset.     

MDP algorithms for portfolio optimization problems in pure jump markets

We consider the problem of maximizing the expected utility of the terminal wealth of a portfolio in a continuous-time pure jump market with general utility function. This leads to an optimal control problem for piecewise deterministic Markov processes. Using an embedding procedure we solve the problem by looking at a discrete-time contracting Markov decision process. Our aim is to show that this point of view has a number of advantages, in particular as far as computational aspects are concerned. We characterize the value function as the unique fixed point of the dynamic programming operator and prove the existence of optimal portfolios. Moreover, we show that value iteration as well as Howard’s policy improvement algorithm works. Finally, we give error bounds when the utility function is approximated and when we discretize the state space. A numerical example is presented and our approach is compared to the approximating Markov chain method.      

Investor preferences and portfolio selection: is diversification an appropriate strategy?

This paper analyzes the relationship between diversification and several distributional characteristics that have risk implications for stock returns. We develop a flexible three-parameter distribution to model the stock returns. Using data on the current 30 DJIA stocks, we show that an investor's strategy on diversification depends on the measures of risk for particular concerns. For example, investors who desire to increase positive skewness would hold a less diversified portfolio, while those who care more about extreme losses would hold a more diversified portfolio. Experimenting with a more general pool of stocks yields the same conclusions.     

What drives portfolio investments of German banks in emerging capital markets?

After decades of steady liberalization and financial market development, emerging capital markets experienced unparalleled capital inflows in the aftermath of the emerging markets crisis of the 1990s. This paper studies portfolio investment decisions of German banks in emerging capital markets from 2002 to 2007. The use of a dynamic time-series cross-section framework and the micro database External Position Report provided by Deutsche Bundesbank permit insights into the various determinants of portfolio investments in ECMs. For example, there is evidence that German banks take into account the various dimensions of financial market development in their portfolio investment decisions and anticipate the special risks inherent in emerging markets. Proxies for the overall development and efficiency of capital markets have the highest economic significance of all variables. The introduction of depositary receipts programs has a positive impact on stock market investment. Moreover, there is evidence that global risk aversion exerts a significant influence in times of financial turmoil.     

Audit committee performance: ownership vs.independence – Did SOX get it wrong?

This study documents a positive relationship between audit committee stock ownership and firm performance in large US firms from 1998 to 2008. This study also finds a positive relationship between changes in ownership and performance. These results persist throughout the sample period, do not weaken after Sarbanes–Oxley and are robust to controlling for endogeneity between ownership and performance. After testing shows that there is no relationship between audit committee independence and firm performance, these findings suggest that audit committee stock ownership is an important corporate governance mechanism and potentially a more relevant variable than audit committee independence from a policy perspective.     

Are good financial advisors really good? The performance of investment banks in the M&;A market

The study examines whether prestigious investment banks deliver quality gains to their clients in a sample of 6,379 US M&A deals. It finds that acquirers advised by tier-one advisors lost more than $42 billion, whereas those advised by tier-two advisors gained $42 billion, whereas those advised by tier-two advisors gained 13.5 billion at the merger announcement. The results were mainly driven by the large loss deals advised by tier-one advisors. The evidence indicates that investment banks might have different incentives when they advise on large deals vs. small deals. The results imply that market share based reputation league tables, could be misleading and therefore, the selection of investment banks should be based on their track record in generating gains to their clients. The findings were consistent with the superior deal hypothesis as tier-one target advisors outperformed tier-two advisors and the existence of a prestigious advisor on at least one side of an M&A transaction resulted in higher wealth gains to the combined entity. Target advisors were able to extract more wealth gains for their clients, which led to higher combined gains at the expense of the acquirer.     

Background filtrations and canonical loss processes for top-down models of portfolio credit risk

In single-obligor default risk modeling, using a background filtration in conjunction with a suitable embedding hypothesis (generally known as ℍ-hypothesis or immersion property) has proven a very successful tool to separate the actual default event from the model for the default arrival intensity. In this paper we analyze the conditions under which this approach can be extended to the situation of a portfolio of several obligors, with a particular focus on the so-called top-down approach. We introduce the natural ℍ-hypothesis of this setup (the successive ℍ-hypothesis) and show that it is equivalent to a seemingly weaker one-step ℍ-hypothesis. Furthermore, we provide a canonical construction of a loss process in this setup and provide closed-form solutions for some generic pricing problems. Financial support by the National Centre of Competence in Research “Financial Valuation and Risk Management” (NCCR FINRISK) is gratefully acknowledged. NCCR FINRISK is a research program supported by the Swiss National Science Foundation (SNSF). The authors would like to thank Monique Jeanblanc and two anonymous referees for their helpful comments and suggestions. Parts of this paper were presented at RiskDay 2006, Zurich. All remaining errors are our own. Comments and suggestions are very welcome.     

Do investors value smooth performance?

This paper presents empirical evidence that cash-flow volatility is negatively valued by investors. The magnitude of the effect is substantial with a 1% increase in cash-flow volatility, resulting in approximately a 0.15% decrease in firm value. We show that this increase, however, is not associated with earnings smoothing resulting from managers’ accrual estimates. Our results are consistent with a preference by the market for less volatile cash flows and suggest that managers’ efforts to produce smooth financial statements add value, but only via the cash component of earnings.