
MML-05-06: Matrix Condition Number, Ill-Conditioning & Numerical Regularization
30 worked single-select and multiselect questions. Tier 2–3. Prerequisites: QS 5.5. Learning goals: Compute Euclidean condition numbers from extreme singular values; Distinguish absolute scale from relative sensitivity; Apply right-hand-side perturbation bounds with fixed invertible matrix; Diagnose anisotropic noise amplification and numerical rank; Compare normal-equation conditioning with the original system; Derive ridge normal equations and singular-direction filters; Quantify regularization stability and bias tradeoffs. Column gradients and output-by-input Jacobians are used where relevant. Detailed solutions explain every choice. References: [Source 1](https://mml-book.github.io/book/mml-book.pdf), [Source 2](https://www.ee.iitm.ac.in/uday/notes/linalg/orth.html), [Source 3](https://mml-book.github.io/book/mml-book.pdf). Ridge reference: [UBC Stat406](https://ubc-stat.github.io/stat-406/schedule/lectures/lecture_06_ridge_regression.html).
Oct 31, 2026










