Data Science & ML
Advanced

Softmax Function

Converts a vector of scores into a probability distribution.

Formula

σ(zi)=ezi∑j=1Kezj\sigma(z_i) = \frac{e^{z_i}}{\sum_{j=1}^{K} e^{z_j}}

Variables

z_iScore for class i
KNumber of classes

Example

Scores [1,2,3] give ~[0.09, 0.24, 0.67]

Did You Know?

Softmax outputs always sum to 1, making them interpretable as probabilities.

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