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I have seen the plot below in many textbooks before. What do the X axis and the Y axis represent exactly? What does it mean for the Hinge loss to "touch" the 0-1 loss on the (x,y) pair (0,1)?

If helpful, the source of this picture is from the entry on Hinge Loss on Wikipedia.

Josh
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1 Answers1

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The x-axis is the score output from a classifier, often interpreted as the estimated/predicted log-odds. The y-axis is the loss for a single datapoint with true label $y = 1$.

In notation, if we denote the score output from the classifier as $\hat s$, the plots are the graphs of the functions:

$$ f(\hat s) = \text{Zero-One-Loss}(\hat s, 1) $$ $$ f(\hat s) = \text{Hinge-Loss}(\hat s, 1) $$

Matthew Drury
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