introduction to pattern recognition. pattern recognition

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Introduction to Pattern Recognition

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Page 1: Introduction to Pattern Recognition. Pattern Recognition

Introduction to Pattern Recognition

Page 2: Introduction to Pattern Recognition. Pattern Recognition

Pattern Recognition

Page 3: Introduction to Pattern Recognition. Pattern Recognition

What is pattern recognition?

A pattern is an object, process or event that can be given a name.

A pattern class (or category) is a set of patterns sharing common attributes and usually originating from the same source.

During recognition (or classification) given objects are assigned to prescribed classes.

A classifier is a machine which performs classification.

“The assignment of a physical object or event to one of several prespecified categeries” -- Duda & Hart

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Examples of applications

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Overfitting and underfitting

Problem: how rich class of classifications q(x;θ) to use.

underfitting overfittinggood fit

Problem of generalization: a small emprical risk Remp does not imply small true expected risk R.

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