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贝叶斯非参数模型序列MCMC推理的有序断棒先验

Ordered Stick-Breaking Prior for Sequential MCMC Inference of Bayesian Nonparametric Models
课程网址: http://videolectures.net/icml2015_das_nonparametric_models/  
主讲教师: Mrinal Kanti Das
开课单位: 印度班加罗尔科学学院
开课时间: 2015-12-05
课程语种: 英语
中文简介:
本文介绍了有序断棒过程(OSBP),其中断棒过程中的原子按顺序出现。OSBP原子重量的选择确保:;(1) 增加新原子的概率呈指数下降,(2)OSBP虽然不可交换,但允许预测概率函数(PPF)。在贝叶斯非参数(BNP)设置中,OSBP作为顺序小批量的自然先验,通过共享OSBP的原子来促进相关统计信息的交换。本文的主要贡献之一是SUMO,一种MCMC算法,用于解决将OSBP应用于BNP模型所产生的推理问题。SUMO使用OSBP的PPF来获得基于吉布斯采样的无截断算法,该算法通常适用于BNP模型。对于大规模推理问题,现有的算法(如粒子滤波(PF))并不实用,变分程序(如TSVI)(Wang\&Blei,2012)是唯一的选择。对于Dirichlet过程混合模型(DPMM),SUMO在具有百万个数据点的3个数据集上的复杂度优于TSVI 33%,这超出了PF的范围,仅使用3GB RAM。
课程简介: This paper introduces ordered stick-breaking process (OSBP), where the atoms in a stick-breaking process (SBP) appear in order. The choice of weights on the atoms of OSBP ensure that; (1) probability of adding new atoms exponentially decrease, and (2) OSBP, though non-exchangeable, admit predictive probability functions (PPFs). In a Bayesian nonparametric (BNP) setting, OSBP serves as a natural prior over sequential mini-batches, facilitating exchange of relevant statistical information by sharing the atoms of OSBP. One of the major contributions of this paper is SUMO, an MCMC algorithm, for solving the inference problem arising from applying OSBP to BNP models. SUMO uses the PPFs of OSBP to obtain a Gibbs-sampling based truncation-free algorithm which applies generally to BNP models. For large scale inference problems existing algorithms such as particle filtering (PF) are not practical and variational procedures such as TSVI (Wang \& Blei, 2012) are the only alternative. For Dirichlet process mixture model (DPMM), SUMO outperforms TSVI on perplexity by 33\% on 3 datasets with million data points, which are beyond the scope of PF, using only 3GB RAM.
关 键 词: 有序断棒过程; 概率函数; 混合模型
课程来源: 视频讲座网
数据采集: 2022-11-08:chenjy
最后编审: 2022-11-08:chenjy
阅读次数: 25