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arXiv 1209.6342stat.MLcs.LG
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具有协变量的稀疏Ising模型

Sparse Ising Models with Covariates

University of Michigan(密歇根大学);Fred Hutchinson Cancer Research Center(弗雷德·哈钦森癌症研究中心)

Jie Cheng, Elizaveta Levina, Pei Wang, Ji Zhu

摘要:

为了理解变量之间的条件依赖关系,已经有大量的工作将伊辛模型拟合到多变量二进制数据。然而,额外的协变量经常与二进制数据一起记录,并且可能影响依赖关系。出于这样一个数据集的基因组不稳定性收集的几种类型的肿瘤样本,我们提出了一个稀疏的协变量依赖伊辛模型研究的条件依赖性的二进制数据及其与其他协变量的关系。这导致了特定于受试者的伊辛模型,其中受试者的协变量影响基因之间的关联强度。在所有探索性数据分析中,结果的可解释性很重要,我们使用L1罚分来诱导拟合图和选定协变量数量的稀疏性。提出了两种模型拟合算法,并在一组模拟数据上进行了比较,建立了渐近结果。肿瘤数据集上的结果及其生物学意义进行了详细讨论。

英文摘要:

There has been a lot of work fitting Ising models to multivariate binary data in order to understand the conditional dependency relationships between the variables. However, additional covariates are frequently recorded together with the binary data, and may influence the dependence relationships. Motivated by such a dataset on genomic instability collected from tumor samples of several types, we propose a sparse covariate dependent Ising model to study both the conditional dependency within the binary data and its relationship with the additional covariates. This results in subject-specific Ising models, where the subject's covariates influence the strength of association between the genes. As in all exploratory data analysis, interpretability of results is important, and we use L1 penalties to induce sparsity in the fitted graphs and in the number of selected covariates. Two algorithms to fit the model are proposed and compared on a set of simulated data, and asymptotic results are established. The results on the tumor dataset and their biological significance are discussed in detail.

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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