2.220446e-16 ≈ 0 [Design Issues]

posted by PharmCat  – Russia, 2019-12-24 14:18 (637 d 22:02 ago) – Posting: # 21025
Views: 4,174

» » » For observation 8 we have -3.608225e-16, I think,
» » I think, is around the "effective zero" for fits in R at default settings on 64- and 32-bit systems.

Hi Helmut!

I suppose hat this value come from QR decomposition with pivoting of rank deficient X matrix. So real value = 0. Can residual of random variable be equal zero? - No => bias.

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