稀疏高斯过程回归变分模型的选择Variational Model Selection for Sparse Gaussian Process Regression |
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课程网址: | http://videolectures.net/bark08_titsias_vmsfsgpr/ |
主讲教师: | Michalis K. Titsias |
开课单位: | 曼彻斯特大学 |
开课时间: | 2008-10-09 |
课程语种: | 英语 |
中文简介: | 稀疏高斯过程(GP)模型的模型选择是涉及选择诱导/活动变量和核参数的重要问题。我们描述了稀疏GP回归的辅助变分方法,它通过最小化近似分布和潜在函数值的真实后验之间的Kullback-Leibler散度来联合学习诱导变量和核参数。使用诱导变量和条件GP先验的无约束分布来参数化变分分布。该框架允许我们计算真实对数边际似然的下限,其可以在诱导输入和内核参数上可靠地最大化。我们将展示如何根据上述框架重新构建几种最先进的稀疏GP方法,例如数据子集(SD),DTC,FITC和PITC方法。 |
课程简介: | Model selection for sparse Gaussian process (GP) models is an important problem that involves the selection of both the inducing/active variables and the kernel parameters. We describe an auxiliary variational method for sparse GP regression that jointly learns the inducing variables and kernel parameters by minimizing the Kullback-Leibler divergence between an approximate distribution and the true posterior over the latent function values. The variational distribution is parametrized using an unconstrained distribution over inducing variables and a conditional GP prior. This framework allows us to compute a lower bound of the true log marginal likelihood which can be reliably maximized over the inducing inputs and the kernel parameters. We will show how we can reformulate several of the most advanced sparse GP methods, such as the subset of data (SD), DTC, FITC and PITC method, based on the above framework. |
关 键 词: | 稀疏高斯过程; GP回归; 变分分布 |
课程来源: | 视频讲座网 |
最后编审: | 2020-06-29:zyk |
阅读次数: | 234 |