The Annals of Applied Probability

Bounding the generalization error of convex combinations of classifiers: balancing the dimensionality and the margins

Vladimir Koltchinskii, Dmitriy Panchenko, and Fernando Lozano

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Abstract

A problem of bounding the generalization error of a classifier %\break $f\in \conv(\mathcal{H})$, where $\mathcal{H}$ is a "base" class of functions (classifiers), is considered. This problem frequently occurs in computer learning, where efficient algorithms that combine simple classifiers into a complex one (such as boosting and bagging) have attracted a lot of attention. Using Talagrand's concentration inequalities for empirical processes, we obtain new sharper bounds on the generalization error of combined classifiers that take into account both the empirical distribution of "classification margins" and an "approximate dimension" of the classifiers, and study the performance of these bounds in several experiments with learning algorithms.

Article information

Source
Ann. Appl. Probab., Volume 13, Number 1 (2003), 213-252.

Dates
First available in Project Euclid: 16 January 2003

Permanent link to this document
https://projecteuclid.org/euclid.aoap/1042765667

Digital Object Identifier
doi:10.1214/aoap/1042765667

Mathematical Reviews number (MathSciNet)
MR1951998

Zentralblatt MATH identifier
1073.62535

Subjects
Primary: 62G05: Estimation
Secondary: 62G20: Asymptotic properties 60F15: Strong theorems

Keywords
Generalization error combined classifier margin approximate dimension empirical process Rademacher process random entropies concentration inequalities boosting bagging

Citation

Koltchinskii, Vladimir; Panchenko, Dmitriy; Lozano, Fernando. Bounding the generalization error of convex combinations of classifiers: balancing the dimensionality and the margins. Ann. Appl. Probab. 13 (2003), no. 1, 213--252. doi:10.1214/aoap/1042765667. https://projecteuclid.org/euclid.aoap/1042765667


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  • ALBUQUERQUE, NEW MEXICO 87131-1141 E-MAIL: vlad@math.unm.edu panchenk@math.unm.edu F. LOZANO DEPARTMENT OF ELECTRONIC ENGINEERING UNIVERSIDAD JAVERIANA BOGOTA COLOMBIA E-MAIL: fernando.lozano@javeriana.edu.co