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对最优秀的遗憾和遗憾的平均

Regret to the Best vs. Regret to the Average
课程网址: http://videolectures.net/otee06_dar_rbvra/  
主讲教师: Eyal Even Dar
开课单位: 宾夕法尼亚大学
开课时间: 2007-02-25
课程语种: 英语
中文简介:
我们研究后悔最小化算法,不仅关注他们对最好的专家的遗憾,而且关注他们对所有专家和最差专家的平均值的遗憾。我们证明,在最坏的情况下,任何只有O(pT)对最佳专家感到遗憾的算法都必须对平均值感到遗憾(pT),并且对于包含许多现有无后悔算法的广泛类别的更新规则(如加权多数,指数权重,跟随扰动的领导者等),遗憾的产品和对平均值的遗憾是(T)。我们基于指数权重算法描述和分析一种新算法,该算法仅向最佳专家实现累积后悔O(pT log(T))并且对平均值具有恒定的遗憾(不依赖于T或N) 。我们还给出了一个简单的算法,其收益总是比最差的专家更好(或相等),并且对最优秀的专家感到遗憾O(pT)。
课程简介: We study regret minimization algorithms, focusing not only on their regret to the best expert, but also on their regret to the average of all experts and to the worst expert. We show that any algorithm that achieves only O(pT) regret to the best expert must, in the worst case, suffer regret (pT) to the average, and that for a wide class of update rules that includes many existing no-regret algorithms (such as weighted majority, exponential weights, follow the perturbed leader, and others), the product of the regret to the best and the regret to the average is (T). We describe and analyze a new algorithm, based on the exponential weights algorithm, that achieves cumulative regret only O(pT log(T)) to the best expert and has a constant regret to the average (with no dependence on either T or N). We also give a simple algorithm whose payoff is always better (or equal) to the worst expert and has regret of O(pT) to the best expert.
关 键 词: 加权多数; 指数权重; 指数权重算法
课程来源: 视频讲座网
最后编审: 2020-06-08:wuyq
阅读次数: 53