\documentclass[11pt]{article} \setlength{\oddsidemargin}{0.0truein} \setlength{\evensidemargin}{0.0truein} \setlength{\textwidth}{6.5truein} \setlength{\topmargin}{0.0truein} \setlength{\textheight}{9.0truein} \setlength{\headsep}{0.0truein} \setlength{\headheight}{0.0truein} \setlength{\topskip}{10.0pt} \setlength{\parskip}{5mm} \usepackage{url} \usepackage{amsmath} \usepackage{amssymb} \pagestyle{empty} \begin{document} \begin{center} \textbf{\Large{\textsc{STANFORD UNIVERSITY}}}\\[5pt] \textbf{\Large{\textsc{DEPARTMENT OF STATISTICS}}}\\[5pt] \Large{\textsc{DEPARTMENTAL SEMINAR}} \end{center} % In the following statements, replace "Time of talk", % "Weekday", and "Date of talk". An example is provided. % If you are not sure about this, just skip this part. \begin{center} 4:15 p.m., Tuesday, March 4, 2008\\ %% Example: 4:15 p.m., Tuesday, February 13, 2007\\ Sequoia Hall Room 200\\ (Cookies at 3:45 in 1st Floor Lounge) \end{center} % In the following statements, replace "Name of the speaker" with your % name, "Department Affiliation" with your department affiliation, and %"University Affiliation" with your university affiliation. \begin{center} \textsl{Peter Hoff} \\ Departments of Statistics and Biostatistics \\ University of Washington \end{center} % In the following statements, replace "Title of the talk" % with your title of the talk. \begin{center} \subsection*{Hierarchical eigenmodels for matrix-valued data} \end{center} % In the following statements, replace "Abstract of the talk" % with your abstract. \noindent Matrix decomposition models are a popular way to represent % and summarize matrix-valued data. For example, the variation among the entries of an $n\times p$ data matrix $Y$ is often expressed using a singular value decomposition model $Y\sim U D V^T +E$, where $U$ and $V$ are orthonormal matrices and $D$ is a diagonal matrix. In this work I consider pooling information across multiple such data matrices $Y^{(1)},\ldots Y^{(K)}$ for situations in which common columns across matrices represent repeated measurements under a common set of conditions. For example, suppose individuals from several different groups have expression levels measured across a common set of genes. If $y_{i,j}^{(k)}$ is the expression level of gene $j$ for patient $i$ in group $k$, then it might be beneficial to share information about the column variation across the different groups. I propose doing this by estimating the parameters in a model for the variability among the orthonormal eigenvector matrices $V^{(1)},\ldots, V^{(K)}$ of the $K$ data matrices. The model is based on a variation of the matrix Bingham distribution, for which estimation is accomplished primarily with Gibbs sampling. The methodology is applied to the analysis of several multiple multivariate datasets. \end{document}