Fast Computation of Leave-One-Out Cross-Validation for $k$-NN Regression

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: Kanagawa, Motonobu
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913597624418304
author Kanagawa, Motonobu
author_facet Kanagawa, Motonobu
contents We describe a fast computation method for leave-one-out cross-validation (LOOCV) for $k$-nearest neighbours ($k$-NN) regression. We show that, under a tie-breaking condition for nearest neighbours, the LOOCV estimate of the mean square error for $k$-NN regression is identical to the mean square error of $(k+1)$-NN regression evaluated on the training data, multiplied by the scaling factor $(k+1)^2/k^2$. Therefore, to compute the LOOCV score, one only needs to fit $(k+1)$-NN regression only once, and does not need to repeat training-validation of $k$-NN regression for the number of training data. Numerical experiments confirm the validity of the fast computation method.
format Preprint
id arxiv_https___arxiv_org_abs_2405_04919
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Fast Computation of Leave-One-Out Cross-Validation for $k$-NN Regression
Kanagawa, Motonobu
Machine Learning
Data Structures and Algorithms
Computation
Methodology
We describe a fast computation method for leave-one-out cross-validation (LOOCV) for $k$-nearest neighbours ($k$-NN) regression. We show that, under a tie-breaking condition for nearest neighbours, the LOOCV estimate of the mean square error for $k$-NN regression is identical to the mean square error of $(k+1)$-NN regression evaluated on the training data, multiplied by the scaling factor $(k+1)^2/k^2$. Therefore, to compute the LOOCV score, one only needs to fit $(k+1)$-NN regression only once, and does not need to repeat training-validation of $k$-NN regression for the number of training data. Numerical experiments confirm the validity of the fast computation method.
title Fast Computation of Leave-One-Out Cross-Validation for $k$-NN Regression
topic Machine Learning
Data Structures and Algorithms
Computation
Methodology
url https://arxiv.org/abs/2405.04919