Improved Boosting Performance by Exclusion of Ambiguous Positive Examples

Miroslav Kobetski, Josephine Sullivan

Abstract

In visual object class recognition it is difficult to densely sample the set of positive examples. Therefore, frequently there will be areas of the feature space that are sparsely populated, in which uncommon examples are hard to disambiguate from surrounding negatives without overfitting. Boosting in particular struggles to learn optimal decision boundaries in the presence of such hard and ambiguous examples. We propose a twopass dataset pruning method for identifying ambiguous examples and subjecting them to an exclusion function, in order to obtain more optimal decision boundaries for existing boosting algorithms. We also provide an experimental comparison of different boosting algorithms on the VOC2007 dataset, training them with and without our proposed extension. Using our exclusion extension improves the performance of all the tested boosting algorithms except TangentBoost, without adding any additional test-time cost. In our experiments LogitBoost performs best overall and is also significantly improved by our extension. Our results also suggest that outlier exclusion is complementary to positive jittering and hard negative mining.

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Paper Citation


in Harvard Style

Kobetski M. and Sullivan J. (2013). Improved Boosting Performance by Exclusion of Ambiguous Positive Examples . In Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM, ISBN 978-989-8565-41-9, pages 11-21. DOI: 10.5220/0004204400110021


in Bibtex Style

@conference{icpram13,
author={Miroslav Kobetski and Josephine Sullivan},
title={Improved Boosting Performance by Exclusion of Ambiguous Positive Examples},
booktitle={Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM,},
year={2013},
pages={11-21},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004204400110021},
isbn={978-989-8565-41-9},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM,
TI - Improved Boosting Performance by Exclusion of Ambiguous Positive Examples
SN - 978-989-8565-41-9
AU - Kobetski M.
AU - Sullivan J.
PY - 2013
SP - 11
EP - 21
DO - 10.5220/0004204400110021