Open access
Jul 2026
On the Optimality of k=n in k-Nearest Neighbor Classification: Sub-Optimality Rates, Dimension-Aware Selection, and Hassanat Distance Comparison
The theoretical results provide a principled non-cross-validated alternative to the classical n rule, and cross-validation remains the strongest k-selection strategy when computationally feasible.
Ahmad Hassanat, A. A. Alkasasbeh, Esra’a Alkafaween et al.
· Mathematics · 1 citation