结构稀疏的增压Boosting with Structural Sparsity |
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课程网址: | http://videolectures.net/icml09_duchi_bwss/ |
主讲教师: | John Duchi |
开课单位: | 加州大学 |
开课时间: | 2009-08-26 |
课程语种: | 英语 |
中文简介: | 我们导出了AdaBoost和相关的基于梯度的坐标下降方法的推广,这些方法结合了对正在学习的预测器范数的稀疏性促进惩罚。最终的结果是一系列坐标下降算法,通过正则化将前向特征归纳和后向修剪结合起来,并为特征归纳提供自动停止标准。我们根据ℓ1.ℓ2,以及ℓ ∞ 并引入基于初始惩罚的混合标准惩罚。混合范数正则化器促进了参数空间中的结构稀疏性,这在多类预测和其他相关任务中是一个有用的特性。我们报告了实证结果,证明了我们的方法在构建精确和结构稀疏模型方面的威力。 |
课程简介: | We derive generalizations of AdaBoost and related gradient-based coordinate descent methods that incorporate sparsity-promoting penalties for the norm of the predictor that is being learned. The end result is a family of coordinate descent algorithms that integrate forward feature induction and back-pruning through regularization and give an automatic stopping criterion for feature induction. We study penalties based on the ℓ1 , ℓ2 , and ℓ ∞ norms of the predictor and introduce mixed-norm penalties that build upon the initial penalties. The mixed-norm regularizers facilitate structural sparsity in parameter space, which is a useful property in multiclass prediction and other related tasks. We report empirical results that demonstrate the power of our approach in building accurate and structurally sparse models. |
关 键 词: | 结构稀疏; 坐标下降; 参数空间 |
课程来源: | 视频讲座网 |
数据采集: | 2023-03-13:chenjy |
最后编审: | 2023-03-13:chenjy |
阅读次数: | 29 |