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Encyclopedia > PAC Learning

Probably approximately correct learning (PAC learning) is a framework of learning that was proposed by Leslie Valiant in his paper A theory of the learnable. Leslie Valiant was educated at Kings College, Cambridge, Imperial College London; and at Warwick University where he received his Ph. ...


In this framework the learner gets samples that are classified according to a function from a certain class. The aim of the learner is to find a bounded approximation (approximately) of the function with high probability (probably). The learner must be able to learn the concept given any arbitrary approximation ratio, probability of success, or distribution of the samples.


The model was further extended to treat noise (misclassified samples). The PAC framework allowed accurate mathematical analysis of learning.


Also critical are definitions of efficiency. In particular, finding efficient classifiers (time and space requirements bounded to a polynomial of the example size) with efficient learning procedures (requiring an example count bounded to a polynomial of the concept size, modified by the approximation and likelihood bounds).


PAC learning framework is part of computational learning theory. In statistics, computational learning theory is a mathematical field related to the analysis of machine learning algorithms. ...


References

  1. L. Valiant. A theory of the learnable. Communications of the ACM, 27, 1984. The paper that proposed the PAC learning framework.
  2. M. Kearns, U. Vazirani. An Introduction to Computational Learning Theory. MIT Press, 1994. A textbook.

External link

  • Probably Approximately Correct Learning - excellent introduction to the topic


 

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