We review how to describe ellipsoids and formulate an optimization problem to enclose sets of points inside an ellipsoid with minimal volume.
1Searching for Robust Markowitz Portfolios: Part I
12 February 2024
We explore whether the framework of Robust Optimization can help us create good portfolios when we are uncertain about future returns.
2The Sample Efficiency of Markowitz Portfolios
27 January 2024
It's bad...
3The Sharpe Ratio: It Ain't That Sharp
20 January 2024
We review the definition of Sharpe ratio, a widely used metric to measure portfolio performance. We show, when it works, how to create portfolios that optimize for it, and its potentially fatal drawbacks.
4Portfolio Construction: Kelly vs Markowitz
15 January 2024
We briefly review a common approach to portfolio construction based on balancing mean and variance. Then we establish a connection with what Kelly taught us about optimal gambling. Finally, with simulations, I show how one can get wrecked using these tools under the presence of fat tails.
523 November 2023
We derive and discuss the Kelly Criterion, a formula for betting optimally and achieving exponential wealth growth.
6Why You Should Never Buy High Dimensional Watermelons
12 November 2023
We explore the distribution of the volume of high dimensional spheres.
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