ytm.guided.backends.act_loss.FocalCE

class ytm.guided.backends.act_loss.FocalCE(alpha: float = 1.0, gamma: float = 2.0, eps: float = 1e-7)

Bases: ActLoss

Softmax with focal cross-entropy, for imbalanced single-label classification.

Parameters:

alphafloat, default=1.0

Overall weight, must be >= 0.

gammafloat, default=2.0

Focusing exponent, must be >= 0. 0 gives cross-entropy.

epsfloat, default=1e-7

Added inside the log and floors 1 - p, must be > 0.