diff --git a/README.md b/README.md index 9ff6872f..17268704 100644 --- a/README.md +++ b/README.md @@ -92,15 +92,11 @@ factor space. The variance for a position $w$ is the sum of the variance of the systematic returns explained by the factors and the variance of the idiosyncratic returns. -```math -Var(r) = Var(\beta^T w) + Var(\epsilon w) -``` +$$Var(r) = Var(\beta^T w) + Var(\epsilon w)$$ We assume the residual returns are uncorrelated and hence -```math -Var(r) = y^T \Sigma_f y + \sum_i w_i^2 Var(\epsilon_i) -``` +$$Var(r) = y^T \Sigma_f y + \sum_i w_i^2 Var(\epsilon_i)$$ where $\Sigma_f$ is the covariance matrix of the factors and $Var(\epsilon_i)$ is the variance of the idiosyncratic returns.