March 19, 2023

Classification

Classification as Regression?

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Class 1 and class 2 are more similar, class1 and class3 are not so similar.

1 Class as one-hot vector

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2 Regression v.s. Classification

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3 Soft-max

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More commonly, it is always use sigmoid when binary classification (only 2 class), but sigmoid and soft-max are equivalent.

4 Loss of Classification

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Minimizing cross-entropy is equivalent to maximizing likelihood.

In Pytorch, when you call cross-entropy, it will include soft-max.

Changing the loss function can change the difficulty of optimization.

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5 Classification

5.1 Function with Unknow Parameters

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5.2 Loss of a function

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5.3 Training Examples

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What do we want?

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Probability of Failure

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Tradeoff of Model Complexity -> Deep Learning

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# ML