MML-05-07: Non-negative Matrix Factorization (NMF) & QR Factorization – Practice Quiz

30 worked single-select and multiselect questions. Tier 2–3. Prerequisites: QS 5.6. Learning goals: Interpret reduced QR dimensions and triangular solves; Compute small QR factorizations and least-squares coefficients; Diagnose rank and numerical-stability issues in QR; Formulate NMF with nonnegative data and factors; Distinguish joint nonconvexity from fixed-factor convexity; Compute Euclidean multiplicative updates with stated assumptions; Interpret additive components and factor nonuniqueness. Column gradients and output-by-input Jacobians are used where relevant. Detailed solutions explain every choice. References: Source 1, Source 2, Source 3.