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非参数非平稳性的高斯过程产品模型

Gaussian Process Product Models for Nonparametric Nonstationarity
课程网址: http://videolectures.net/icml08_stegle_gpp/  
主讲教师: Oliver Stegle
开课单位: 马克斯普朗克研究所
开课时间: 2008-07-29
课程语种: 英语
中文简介:
对于高斯过程回归,平稳性通常是不现实的先验假设。一种解决方案是预定义明确的非平稳协方差函数,但是这种协方差函数可能难以指定并且需要详细的非平稳性的先验知识。我们提出高斯过程产品模型(GPPM),其将数据建模为两个潜在高斯过程的点积,以非参数推断非平稳的幅度变化。该方法与协方差函数推断的其他非参数方法的不同之处在于,它对输出而不是输入进行操作,从而显着降低了计算成本和所需的推理数据,同时提高了对高维输入空间的可扩展性。我们使用期望传播提出近似推理方案。这种变分近似产生了方便的GP超参数选择和紧凑的近似预测分布。
课程简介: Stationarity is often an unrealistic prior assumption for Gaussian process regression. One solution is to predefine an explicit nonstationary covariance function, but such covariance functions can be difficult to specify and require detailed prior knowledge of the nonstationarity. We propose the Gaussian process product model (GPPM) which models data as the pointwise product of two latent Gaussian processes to nonparametrically infer nonstationary variations of amplitude. This approach differs from other nonparametric approaches to covariance function inference in that it operates on the outputs rather than the inputs, resulting in a significant reduction in computational cost and required data for inference, while improving scalability to high-dimensional input spaces. We present an approximate inference scheme using Expectation Propagation. This variational approximation yields convenient GP hyperparameter selection and compact approximate predictive distributions.
关 键 词: 高斯过程; 非平稳协方差函数; 近似预测分布
课程来源: 视频讲座网
最后编审: 2019-04-21:lxf
阅读次数: 69