ISM Research Memorandum
No. 1005
Title:
Boosting method for local learning
Author(s):
KAWAKITA, Masanori (The Graduate University of Advanced Studies);
EGUCHI, Shinto (The Graduate University of Advanced Studies)
Key words:
boosting; local likelihood; decision stump; VC dimension;
classification.
Abstract:
We propose a local boosting method in
classification problems borrowing from an idea of the local likelihood method.
The proposed method includes a simple device to localization for computational
feasibility. We proved the Bayes risk consistency of the local boosting in the
framework of PAC learning. Inspection of the proof provides a useful viewpoint
for comparing the ordinary boosting and the local boosting with respect to the
estimation error and the approximation error. Both boosting methods have the
Bayes risk consistency if their approximation errors decrease to zero.
Compared to the ordinary boosting, the local boosting may perform better by
controlling the trade-off between the estimation error and the approximation
error. Several numerical studies on real data sets confirm the advantageous
aspects of the local AdaBoost over AdaBoost.