方法对比

	线性判别分析 (LDA	主成分分析
领域	统计学	机器学习
方法族	Hypothesis test	Machine learning
起源年份	1936	2002
提出者	Ronald A. Fisher	Jolliffe, I.T. (textbook); Pearson & Hotelling (origins)
类型	Parametric linear classifier / dimensionality reduction	Unsupervised dimensionality reduction
开创性文献	Fisher, R.A. (1936). The Use of Multiple Measurements in Taxonomic Problems. Annals of Eugenics, 7(2), 179–188.	Jolliffe, I.T. (2002). Principal Component Analysis (2nd ed.). Springer.
别名	LDA, Fisher's LDA, Fisher's linear discriminant, discriminant function analysis	Temel Bileşenler Analizi (PCA), PCA, principal components analysis, Karhunen-Loève transform
相关	7	3
摘要	Linear Discriminant Analysis (LDA) is a parametric supervised classification method that finds the linear combination of continuous predictors that best separates two or more predefined groups. Introduced by Ronald A. Fisher in his landmark 1936 paper on taxonomic measurements, it simultaneously serves as a classifier and a dimensionality-reduction tool, and can be understood as the classification-oriented counterpart of MANOVA.	Principal Component Analysis (PCA) is an unsupervised dimensionality-reduction method — given its modern textbook treatment by Ian Jolliffe (2002) — that compresses high-dimensional data into fewer dimensions while preserving the maximum possible variance. It re-expresses correlated variables as a small set of uncorrelated principal components ordered by how much of the data's variation each one captures.