Academic reference · Orthogonal Decomposition
Frisch et al. (1933)
Frisch, R., & Waugh, F. V. (1933). Partial time regressions as compared with individual trends. Econometrica, 1(4), 387–401.
Why it matters
The Frisch-Waugh-Lovell theorem is the algebraic basis for residualizing one factor against prior factors before estimating its incremental contribution.