计算机应用 ›› 2012, Vol. 32 ›› Issue (10): 2916-2919.DOI: 10.3724/SP.J.1087.2012.02916

• 人工智能 • 上一篇    下一篇

基于损失函数的AdaBoost改进算法

雷蕾,王晓丹   

  1. 空军工程大学 防空反导学院,陕西 西安 710051
  • 收稿日期:2012-04-25 修回日期:2012-06-14 发布日期:2012-10-23 出版日期:2012-10-01
  • 通讯作者: 雷蕾
  • 作者简介:雷蕾(1988-),女,四川南充人,硕士研究生,主要研究方向:模式识别、智能信息处理;王晓丹(1966-),女,陕西汉中人,教授,博士生导师,主要研究方向:智能信息处理、机器学习。
  • 基金资助:
    国家自然科学基金资助项目

Improved AdaBoost ensemble approach based on loss function

LEI Lei,WANG Xiao-danWANG   

  1. School of Air and Missile Defense, Air Force Enginerring University, XiAn Shaanxi 710051, China
  • Received:2012-04-25 Revised:2012-06-14 Online:2012-10-23 Published:2012-10-01
  • Contact: LEI Lei

摘要: 针对AdaBoost集成时难分样本权重扩张导致训练样本在更新时分布失衡的问题,提出一种基于正负类样本损失函数(LF)的权重更新策略。权重的调整不仅与训练误差有关,还考虑到基分类器对不同类别样本的正确分类能力,从而避免训练样本过度集中于某一类的异常现象。实验结果表明,基于LF的AdaBoost能在提高收敛性能的情况下,提高算法精度,克服样本分布失衡问题。偏差方差分析的结果显示,该算法在改善偏差的情况下,能有效地减小错误率中的方差成分,提高集成的泛化能力。

关键词: AdaBoost算法, 支持向量机, 损失函数

Abstract: As to the issue that the weight expansion for hardest samples can cause imbalance when updating the training sample in AdaBoost algorithm, an improved approach based on the Loss Function (LF) of the different patterns, namely, LF-AdaBoost, was proposed. The weight tuning was affected not only by the training error, but the performance of base classifiers for different classes, thus avoiding the excessive concentration phenomenon. The results based on UCI data sets and different base classifiers have shown that the approach can improve the speed of convergence and overcome the imbalance, as well as promote the generalization ability of ensemble classifier.

Key words: AdaBoost algorithm, Support Vector Machine (SVM), Loss Function (LF)