EnsembleMethods - Chapter 5: Ensemble Methods CSE572,...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style 4/8/10 Chapter 5: Ensemble Methods CSE572, Spring 2010 CSE 572 Spring 2009
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4/8/10 Ensemble Methods Construct a set of classifiers from the training data Predict class label of previously unseen records by aggregating predictions made by multiple classifiers
Background image of page 2
4/8/10 General Idea
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4/8/10 Why does it work? Suppose there are 25 base classifiers Each classifier has error rate, P Assume classifiers are independent ±robability that the ensemble classifier makes a wrong prediction:
Background image of page 4
4/8/10 Examples of Ensemble Methods How to generate an ensemble of classifiers? Bagging Boosting
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4/8/10 Bagging Sampling with replacement Build classifier on each bootstrap sample Each sample has probability 1- (1 – 1/ n)n of being selected Original Data 1 2 3 4 5 6 7 8 9 10 Bagging (Round 1) 7 8 10 8 2 5 10 10 5 9 Bagging (Round 2) 1 4 9 1 2 3 2 7 3 2 Bagging (Round 3) 1 8 5 10 5 5 9 6 3 7
Background image of page 6
4/8/10 Boosting An iterative procedure to adaptively
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/08/2010 for the course CS 420 taught by Professor Dawsonengler during the Spring '02 term at San Jose State University .

Page1 / 12

EnsembleMethods - Chapter 5: Ensemble Methods CSE572,...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online