Glossary · Phase 2 · Math, when you need it
Target
The right answer a model should give for an example, such as the true sale amount. The loss measures how far the prediction is from it.
Try it now
Step through: the forward lines fill in z, a and L; the backward lines multiply local slopes from the loss back to w and b.
Learn it properly
The chain rule · Derivatives of functions inside functions: the heart of backprop. About 30 minutes.
Other terms from the same lesson
- chain rule: To find how a chain of steps responds to a nudge, multiply how much each step responds.
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