diff --git a/src/year1/statistical-and-mathematical-methods-for-ai/sections/_matrix_decomp.tex b/src/year1/statistical-and-mathematical-methods-for-ai/sections/_matrix_decomp.tex index ef2cb08..9b717a7 100644 --- a/src/year1/statistical-and-mathematical-methods-for-ai/sections/_matrix_decomp.tex +++ b/src/year1/statistical-and-mathematical-methods-for-ai/sections/_matrix_decomp.tex @@ -116,7 +116,7 @@ we can construct a rank-1 matrix (dyad) $\matr{A}_i \in \mathbb{R}^{m \times n}$ where $\vec{u}_i \in \mathbb{R}^m$ is the $i$-th column of $\matr{U}$ and $\vec{v}_i \in \mathbb{R}^n$ is the $i$-th column of $\matr{V}$. Then, we can compose $\matr{A}$ as a sum of dyads: -\[ \matr{A}_i = \sum_{i=1}^{r} \sigma_i \vec{u}_i \vec{v}_i^T = \sum_{i=1}^{r} \sigma_i \matr{A}_i \] +\[ \matr{A} = \sum_{i=1}^{r} \sigma_i \vec{u}_i \vec{v}_i^T = \sum_{i=1}^{r} \sigma_i \matr{A}_i \] \marginnote{Rank-$k$ approximation} By considering only the first $k < r$ singular values, we can obtain a rank-$k$ approximation of $\matr{A}$: