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arXiv 1607.00515stat.ME
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多分位数图模型

The Multiple Quantile Graphical Model

Alnur Ali, J. Zico Kolter, Ryan J. Tibshirani

摘要:

我们引入了多分位数图形模型(MQGM),它扩展了Meinshausen和Buhlmann的邻域选择方法,用于学习稀疏图形模型。后者是由一个变量的条件均值建模为所有其他变量的稀疏函数的基本子问题定义的。我们的方法将一个变量的一组条件分位数建模为所有其他变量的稀疏函数,因此提供了更丰富,更有表现力的条件分布估计类。我们建立,在适当的正则条件下,MQGM确定确切的条件独立性与概率倾向于一个问题的大小的增长,即使在通常的同性高斯数据模型。我们开发了一个有效的算法,使用交替方向的乘法器来拟合MQGM。我们还描述了一种策略,从联合分布的MQGM估计的基础抽样。最后,我们提出了详细的实验,证明的灵活性和有效性的MQGM建模异方差非高斯数据。

英文摘要:

We introduce the Multiple Quantile Graphical Model (MQGM), which extends the neighborhood selection approach of Meinshausen and Buhlmann for learning sparse graphical models. The latter is defined by the basic subproblem of modeling the conditional mean of one variable as a sparse function of all others. Our approach models a set of conditional quantiles of one variable as a sparse function of all others, and hence offers a much richer, more expressive class of conditional distribution estimates. We establish that, under suitable regularity conditions, the MQGM identifies the exact conditional independencies with probability tending to one as the problem size grows, even outside of the usual homoskedastic Gaussian data model. We develop an efficient algorithm for fitting the MQGM using the alternating direction method of multipliers. We also describe a strategy for sampling from the joint distribution that underlies the MQGM estimate. Lastly, we present detailed experiments that demonstrate the flexibility and effectiveness of the MQGM in modeling hetereoskedastic non-Gaussian data.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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