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个体贡献排序的合集修剪

Ensemble Pruning via Individual Contribution Ordering
课程网址: http://videolectures.net/kdd2010_lu_epic/  
主讲教师: Zhenyu Lu
开课单位: 佛蒙特大学
开课时间: 2010-10-01
课程语种: 英语
中文简介:
集合是一组共同作出决策的学习模型。虽然集合通常比单个学习者更准确,但是现有的集合方法通常倾向于构造不必要的大集合,这增加了存储器消耗和计算成本。集合修剪通过选择集合成员的子集来形成子问题来解决这个问题,所述子集合具有较少的资源消耗和响应时间,其精度与原始集合相似或更好。在本文中,我们分析了准确性/多样性权衡,并证明在少数群体中更准确和更多预测的分类器对于子群构造更为重要。基于所获得的见解,提出了考虑准确性和多样性的启发式度量,以明确地评估每个单独的分类器对整个集合的贡献。通过按照其贡献的递减顺序合并集合成员,形成子集合,使得用户可以根据其资源可用性和可容忍的等待时间来选择集合成员的最高$ p $百分比用于预测。在26个UCI数据集上的实验结果表明,由所提出的EPIC(通过单独贡献排序的集合修剪)算法形成的子标记优于原始集合和现有技术的集合修剪方法,定向排序(OO)。
课程简介: An ensemble is a set of learned models that make decisions collectively. Although an ensemble is usually more accurate than a single learner, existing ensemble methods often tend to construct unnecessarily large ensembles, which increases the memory consumption and computational cost. Ensemble pruning tackles this problem by selecting a subset of ensemble members to form subensembles that are subject to less resource consumption and response time with accuracy that is similar to or better than the original ensemble. In this paper, we analyze the accuracy/diversity trade-off and prove that classifiers that are more accurate and make more predictions in the minority group are more important for subensemble construction. Based on the gained insights, a heuristic metric that considers both accuracy and diversity is proposed to explicitly evaluate each individual classifier's contribution to the whole ensemble. By incorporating ensemble members in decreasing order of their contributions, subensembles are formed such that users can select the top $p$ percent of ensemble members, depending on their resource availability and tolerable waiting time, for predictions. Experimental results on 26 UCI data sets show that subensembles formed by the proposed EPIC (Ensemble Pruning via Individual Contribution ordering) algorithm outperform the original ensemble and a state-of-the-art ensemble pruning method, Orientation Ordering (OO).
关 键 词: 学习模型; 集合成员; 分类器
课程来源: 视频讲座网
最后编审: 2019-05-11:lxf
阅读次数: 72