presenter : fen-rou, ciou authors : toh koon charlie neo, dan ventura 2012, prl

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Intelligent Database Systems Presenter : Fen-Rou, Ciou Authors : Toh Koon Charlie Neo, Dan Ventura 2012, PRL A direct boosting algorithm for the k-nearest neighbor classifier via local warping of the distance metric

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A direct boosting algorithm for the k-nearest neighbor classifier via local warping of the distance metric. Presenter : Fen-Rou, Ciou Authors : Toh Koon Charlie Neo, Dan Ventura 2012, PRL. Outlines. Motivation Objectives Methodology Experiments Conclusions Comments. Motivation. - PowerPoint PPT Presentation

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Page 1: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Presenter : Fen-Rou, Ciou

Authors : Toh Koon Charlie Neo, Dan Ventura

2012, PRL

A direct boosting algorithm for the k-nearest neighbor classifier via local warping

of the distance metric

Page 2: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

OutlinesMotivationObjectivesMethodologyExperimentsConclusionsComments

Page 3: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Motivation

• The k-nearest neighbor pattern classifier is an

effective learning algorithm, it can result in large

model sizes.

Page 4: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Objectives

• The paper present a direct boosting algorithm for the

k-NN classifier that creates an ensemble of models

with locally modified distance weighting to increase

the accuracy and condense the model size.

Page 5: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Methodology - Framework

AdaBoost

v = {+, }

Dzxi

x

Page 6: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Methodology

Sensitivity data order - Randomize - Batch update

Page 7: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Methodology

Sensitivity data order - Randomize - Batch update

Page 8: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Methodology

Voting mechanism - simple voting - error-weigh voting

Page 9: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Methodology

Condensing model size - optimal weight - average the weight

Page 10: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Experiments

Page 11: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Experiments

Page 12: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Experiments

Fig 8. Boosted k-NN with randomized data order.Fig 9. Boosted k-NN with batch update. Fig 10. Boosted k-NN with error-weighted voting.Fig 11. Boosted k-NN with optimal weights. Fig 12. Boosted k-NN with average weights.

Page 13: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Experiments

Page 14: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Conclusions• The Boosted k-NN can boost the generalization

accuracy of the k-nearest neighbor algorithm.

• The Boosted k-NN algorithm modifier the decision

surface, producing a better solution.

Page 15: Presenter   :  Fen-Rou,  Ciou Authors      :  Toh Koon Charlie Neo, Dan  Ventura 2012, PRL

Intelligent Database Systems Lab

Comments• Advantages– The paper describes rich experiment.

• Applications– classification