VyntriVyntri
Solvers

FK — Friedman's Discriminative Whitening

FK whitening with eigenvalue flooring and diagonal shrinkage.

How It Works

  1. FK Projection — computes discriminative whitening with eigenvalue flooring for numerical stability.
  2. Ridge Regression — fits a linear classifier in the projected space using closed-form solve.

FK is the default adaptation method. It works with continual learning (update()).

Parameters

ParameterDefaultDescription
shrinkage_alpha0.5Diagonal shrinkage intensity
regularization1e-4Ridge regularization strength
Python
from vyntri import Vyntri
from vyntri.data import split

s = split("./my_dataset", train=0.7, test=0.2, seed=42)

# FK is the default adaptation method
model = Vyntri()
model.fit(train=s.train, val=s.val)

# Or explicitly set adaptation="fk"
model = Vyntri(adaptation="fk", shrinkage_alpha=0.5)
model.fit(train=s.train, val=s.val)