Machine Learning: Difference between revisions

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Probably Approximately Correct (PAC)<br>
Probably Approximately Correct (PAC)<br>
A hypothesis class <math>H</math> is PAC learnable if given <math>0 < \epsilon, \delta < 1</math>, there is some function <math>m(\epsilon, \delta)</math> polynomial in <math>1/\epsilon, 1/\delta</math> such that if we have a sample size <math>\geq m(\epsilon, \delta)</math> then with probability <math>1-\delta</math> the hypothesis we will learn will have an average error <math>\leq \epsilon</math>.
A hypothesis class <math>H</math> is PAC learnable if given <math>0 < \epsilon, \delta < 1</math>, there is some function <math>m(\epsilon, \delta)</math> polynomial in <math>1/\epsilon, 1/\delta</math> such that if we have a sample size <math>\geq m(\epsilon, \delta)</math> then with probability <math>1-\delta</math> the hypothesis we will learn will have an average error <math>\leq \epsilon</math>.
===Uniform Convergence===
If for all hypothesis <math>h</math>, <math>|L_S(h)-L_D(h)| \leq \epsilon</math>, then the training set <math>S</math> is called <math>\epsilon</math>-representative.