Staying ahead on downside risk 157
approach tends to underweight the asset compared to mean – variance. Once
again, the main differences are found for the S & P and FTSE indices. By adopt-
ing a mean – EVaR criterion instead of mean – variance, we end up overweighting
the UK index, for the reason explained above: The S & P 500 has experienced
Table 6.5 Actual returns observed for December 2008 and sample moments of the
100 simulated alpha vectorsspx dax nky ukx
Return in December 2008 2.20% 1.51% 3.70% 1.54%
Simulated alphas:
Mean 0.74% 0.45% 1.08% 0.40%
Standard deviation 2.08% 2.84% 2.88% 1.97%806040200806040200Frequency8040503020100FrequencyE-VaR
overweightMean variance
overweight–40 –20 0 20dax ukxnky spxPct points Pct pointsPct points Pct points40 60 80 –40 -20 0 20 40 60 80Frequency35253020
155100Frequency–40 –20 0 20 40 60 80 –40 –20 0 20 40 60 80Figure 6.5 Difference between mean – variance and mean – EVaR allocation.