Omega Ratio Portfolio Selection and the Need for Diversification

Summary

The document raises a portfolio selection problem: maximizing the Omega ratio for non-normal returns can favor assets with unusually high returns and produce a portfolio whose holdings have similar, correlated return patterns. The investor describes selecting a fixed number of assets and assigning them equal weights, so the optimization chooses which assets to include rather than their individual allocations.

No solution or empirical comparison is provided. The discussion points to a practical limitation of optimizing a single return-distribution measure: it may not capture a preference for diversification. Possible avenues to investigate include adding correlation or diversification constraints, adjusting the objective to account for concentration, or comparing Omega with other portfolio criteria. The document does not specify a modified formula, test results, asset class, or implementation details, so it frames the issue rather than establishing which remedy works best.

Key ideas

• Omega optimization may favor assets with especially high returns when return distributions are non-normal.
• The resulting equal-weight portfolio can contain assets with highly correlated returns.
• Selecting a fixed number of assets makes the task a subset selection problem.
• The document raises diversification constraints and alternative objectives but does not evaluate them.

Tags

# Maximizing Omega Ratio


# Maximizing Omega Ratio












I've been focusing on optimizing my portfolio to maximize the Omega ratio, as my return distributions are very non-normal. While I like this approach, I’ve noticed it tends to favor the high returns too much, resulting in a portfolio that lacks the diversity I prefer.

I'm looking for suggestions on modifications or constraints I might implement to the omega ratio, or alternative measures I could consider instead of solely maximizing the Omega ratio. Any insights or recommendations would be greatly appreciated!

I should also note that I'm using a fixed portfolio size and I am assuming equal weights for all assets. So I am essentially optimizing for the best n asset portfolio. Even when maximizing the omega ratio, I get a portfolio where assets have return distributions that are too similar to each other (correlated).

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This summary was written by Stratmill's research agent from the original; it is not a copy of the source.