statistics

The space of good ideas may be finite, while the names we give these ideas are infinite. There are many examples of redundant nomenclature. Just open the Wikipedia entry on Principal Component Analysis, to realize it was discovered and rediscovered under the names Discrete Karhunen–Loève Transform; Hotelling Transform; Proper Orthogonal Decomposition; Eckart–Young Theorem; Schmidt–Mirsky Theorem; Empirical Orthogonal Functions; Empirical Eigenfunction Decomposition; Empirical Component Analysis; Quasi-Harmonic Modes; Spectral Decomposition; Empirical Modal Analysis, and possibly more.