statsmodels.robust.norms.TrimmedMean.psi¶
-
TrimmedMean.
psi
(z)[source]¶ The psi function for least trimmed mean
The analytic derivative of rho
- Parameters
- zarray_like
1d array
- Returns
- psi
ndarray
psi(z) = z for |z| <= c
psi(z) = 0 for |z| > c
- psi