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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">JDS</journal-id>
<journal-title-group><journal-title>Journal of Data Science</journal-title></journal-title-group>
<issn pub-type="epub">1683-8602</issn><issn pub-type="ppub">1680-743X</issn><issn-l>1680-743X</issn-l>
<publisher>
<publisher-name>School of Statistics, Renmin University of China</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">JDS1030</article-id>
<article-id pub-id-type="doi">10.6339/21-JDS1030</article-id>
<article-categories><subj-group subj-group-type="heading">
<subject>Statistical Data Science</subject></subj-group></article-categories>
<title-group>
<article-title>Hierarchical Ridge Regression for Incorporating Prior Information in Genomic Studies</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Kawaguchi</surname><given-names>Eric S.</given-names></name><email xlink:href="mailto:eric.kawaguchi@med.usc.edu">eric.kawaguchi@med.usc.edu</email><xref ref-type="aff" rid="j_jds1030_aff_001">1</xref><xref ref-type="corresp" rid="cor1">∗</xref><xref ref-type="fn" rid="j_jds1030_fn_001">†</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Li</surname><given-names>Sisi</given-names></name><xref ref-type="aff" rid="j_jds1030_aff_001">1</xref><xref ref-type="fn" rid="j_jds1030_fn_001">†</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Weaver</surname><given-names>Garrett M.</given-names></name><xref ref-type="aff" rid="j_jds1030_aff_001">1</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Lewinger</surname><given-names>Juan Pablo</given-names></name><xref ref-type="aff" rid="j_jds1030_aff_001">1</xref>
</contrib>
<aff id="j_jds1030_aff_001"><label>1</label>Department of Population and Public Health Sciences, Keck School of Medicine, <institution>University of Southern California</institution>, Los Angeles, California, <country>USA</country></aff>
</contrib-group>
<author-notes>
<corresp id="cor1"><label>∗</label>Corresponding author. Email: <ext-link ext-link-type="uri" xlink:href="mailto:eric.kawaguchi@med.usc.edu">eric.kawaguchi@med.usc.edu</ext-link>.</corresp><fn id="j_jds1030_fn_001"><label>†</label>
<p>Joint First Author.</p></fn>
</author-notes>
<pub-date pub-type="ppub"><year>2022</year></pub-date><pub-date pub-type="epub"><day>13</day><month>12</month><year>2021</year></pub-date><volume>20</volume><issue>1</issue><fpage>34</fpage><lpage>50</lpage><supplementary-material id="S1" content-type="archive" xlink:href="jds1030_s001.zip" mimetype="application" mime-subtype="x-zip-compressed">
<caption>
<title>Supplementary Materials</title>
<p>.zip contains the following files and/or directories: 
<list>
<list-item id="j_jds1030_li_001">
<label>•</label>
<p><bold>simulations/</bold>: Directory that includes code and files necessary to reproduce the numerical results presented in this paper.</p>
</list-item>
<list-item id="j_jds1030_li_002">
<label>•</label>
<p><bold>supplementary.pdf</bold>: Online supplementary material.</p>
</list-item>
</list>
</p>
</caption>
</supplementary-material><history><date date-type="received"><day>20</day><month>7</month><year>2021</year></date><date date-type="accepted"><day>5</day><month>11</month><year>2021</year></date></history>
<permissions><copyright-statement>2022 The Author(s). Published by the School of Statistics and the Center for Applied Statistics, Renmin University of China.</copyright-statement><copyright-year>2022</copyright-year>
<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
<license-p>Open access article under the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">CC BY</ext-link> license.</license-p></license></permissions>
<abstract>
<p>There is a great deal of prior knowledge about gene function and regulation in the form of annotations or prior results that, if directly integrated into individual prognostic or diagnostic studies, could improve predictive performance. For example, in a study to develop a predictive model for cancer survival based on gene expression, effect sizes from previous studies or the grouping of genes based on pathways constitute such prior knowledge. However, this external information is typically only used post-analysis to aid in the interpretation of any findings. We propose a new hierarchical two-level ridge regression model that can integrate external information in the form of “meta features” to predict an outcome. We show that the model can be fit efficiently using cyclic coordinate descent by recasting the problem as a single-level regression model. In a simulation-based evaluation we show that the proposed method outperforms standard ridge regression and competing methods that integrate prior information, in terms of prediction performance when the meta features are informative on the mean of the features, and that there is no loss in performance when the meta features are uninformative. We demonstrate our approach with applications to the prediction of chronological age based on methylation features and breast cancer mortality based on gene expression features.</p>
</abstract>
<kwd-group>
<label>Keywords</label>
<kwd>high-dimensional regression</kwd>
<kwd>meta-features</kwd>
<kwd>penalization</kwd>
<kwd>prediction</kwd>
<kwd>regularization</kwd>
</kwd-group>
<funding-group><award-group><funding-source xlink:href="https://doi.org/10.13039/100000002">National Institutes of Health</funding-source><award-id>1P01CA196569</award-id><award-id>T32ES013678</award-id></award-group><funding-statement>The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was supported by the National Institutes of Health awards 1P01CA196569 and T32ES013678. These awards had no influence over the experimental design, data analysis or interpretation, or writing the manuscript.</funding-statement></funding-group>
</article-meta>
</front>
<body/>
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