Title
Portfolio value-at-risk optimization for asymmetrically distributed asset returns.
Abstract
We present a new approach to portfolio optimization by separating asset return distributions into positive and negative half-spaces. The approach minimizes a so-called Partitioned Value-at-Risk (PVaR) measure by using the statistical information from the two half-spaces respectively. We show that the proposed PVaR approach is a signiflcant improvement in several important aspects when compared to Markowitz mean-variance optimization approach. First, our approach, which accom- modates ambiguous asymmetric return distributions and captures portfolio risk in higher moments, does not require asset distributions being elliptically symmetric or multivariate normal. Second, using simulated and real data, our approach generates better risk-return tradeofis in the optimal portfolios. The difierence between the two approaches increases in the degree of asymmetry in the underlying asset distributions. Third, when given the support of asset returns, our PVaR measure becomes a coherent risk measure proposed by Artzner et al. (1999) whereas conventional risk measures such as variance and VaR fail to do so. Moreover, our PVaR measure is an asymmetric risk measure, which is difierent from symmetric risk measures like variance and worst-case mean-covariance VaR (WVaR). Therefore, our proposed PVaR is a signiflcant addition to the existing portfolio risk mea- sures. We believe that the PVaR approach can be very useful for better portfolio allocations than the mean-variance or other symmetric risk-metrics approach during market downturns when asset return distributions are often fat-tailed or skewed.
Year
DOI
Venue
2012
10.1016/j.ejor.2012.03.012
European Journal of Operational Research
Keywords
Field
DocType
Risk management,Asymmetric distributions,Partitioned value-at-risk,Portfolio optimization,Robust risk measures
Mathematical optimization,Project portfolio management,Robust optimization,Portfolio,Efficient frontier,Risk management,Portfolio optimization,Risk measure,Value at risk,Mathematics
Journal
Volume
Issue
ISSN
221
2
0377-2217
Citations 
PageRank 
References 
26
1.08
11
Authors
4
Name
Order
Citations
PageRank
Joel Goh11649.07
Kian Guan Lim2605.35
Melvyn Sim31909117.68
Weina Zhang4281.46