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Support Vector Machines. Presented By Sherwin Shaidaee. Papers. Vladimir N. Vapnik, “The Statistical Learning Theory”. Springer, 1998 Yunqiang Chen, Xiang Zhou, and Thomas S. Huang, University of Illinois, “ONE-CLASS SVM FOR LEARNING IN IMAGE RETRIEVAL”, 2001
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Support Vector Machines Presented By Sherwin Shaidaee
Papers • Vladimir N. Vapnik, “The Statistical Learning Theory”. Springer, 1998 • Yunqiang Chen, Xiang Zhou, and Thomas S. Huang, University of Illinois, “ONE-CLASS SVM FOR LEARNING IN IMAGE RETRIEVAL”, 2001 • A. Ganapathiraju, Member, IEEE, J. Hamaker, Member, IEEE and J. Picone, Senior Member, IEEE, ”Applications of Support Vector Machines To Speech Recognition” , 2003
Introduction to Support Vector Machines • SVMs are based on statistical learning theory; the aim being to solve only the problem of interest without solving a more difficult problem as an intermediate step • SVMs are based on the structural risk minimisation principle, which incorporates capacity control to prevent over-fitting
The Separable Case • Two-Class Classification • P: Positive N: Negative for Yi=+1,-1 • The support vector algorithm simply looks for separating hyperplane with largest margin. OR
Convex Quadratic Problem Lagrangian for this problem: where are the Lagrange multipliers
Convex Quadratic Problem Differentiation with respect to w & b:
Support vectors • Lie closest to the separating hyperplane. • Optimal Weights: • Optimal Bias:
Types of Support vectors (a) two-class linear (b) One-class (c) Non-linear Decision Function:
Kernel feature Spaces • Feature space • Decision Function
Image Retrieval An Application for SVM • Relevance Feedback • Problem with small number of training samples and the high dimension of the feature space
Image Retrieval • One-Class SVM • Estimate the distribution of the target images in the feature space without over-fitting to the user feedback.
Experiment • Five Classes: • Airplanes, Cars, Horses, Eagles , Glasses • 100 images for each class • 10 images are randomly drawn as training sample. • Hit rates in the first 20 and 100 images are used as the performance measure.