手法を比較

	偏最小二乗回帰（PLS）	主成分回帰 (PCR)
分野	機械学習	機械学習
系統	Machine learning	Machine learning
提唱年	1975	1982
提唱者	Herman Wold; popularized by Svante Wold in chemometrics	Principal-component regression literature (Jolliffe and others)
種類	Supervised latent-variable regression	Unsupervised dimension reduction + regression
原典	Wold, S., Sjöström, M., & Eriksson, L. (2001). PLS-regression: a basic tool of chemometrics. Chemometrics and Intelligent Laboratory Systems, 58(2), 109–130.	Jolliffe, I. T. (1982). A note on the use of principal components in regression. Journal of the Royal Statistical Society: Series C (Applied Statistics), 31(3), 300–303.
別名	PLS regression, projection to latent structures, PLSR, kısmi en küçük kareler	PCR, PCA regression, temel bileşenler regresyonu
関連	3	3
概要	Partial least squares regression predicts a response from many, often highly collinear predictors by projecting them onto a small set of latent components — but, unlike principal components regression, it chooses those components to maximize their covariance with the response, not just the variance of the predictors. This supervised dimension reduction makes PLS a workhorse in chemometrics, spectroscopy, and other wide-data settings where predictors vastly outnumber observations.	Principal components regression first compresses a set of correlated predictors into a few principal components — the directions of greatest variance — and then regresses the response on those components. By discarding low-variance directions, PCR stabilizes estimation in the presence of multicollinearity and high dimensionality, at the cost of choosing components without reference to the response.