User Tools

Site Tools


seminars:datasci:111522

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
seminars:datasci:111522 [2022/11/09 20:36] gfuseminars:datasci:111522 [2022/11/09 20:37] (current) gfu
Line 1: Line 1:
 +<WRAP centeralign>##Data Science Seminar##\\ Hosted by the Department of Mathematics and Statistics</WRAP>
 +
 +  * Date: Tuesday, November 15, 2022
 +  * Time: 12:00pm -- 1:00pm
 +  * Room: Whitney Hall 100E
 +  * Speaker: Dr. Rachael Hageman Blair (University at Buffalo)
 +  * Title: Harnessing stability estimation for module detection, clustering, and ensemble clustering.
 +
 +<WRAP center box 80%>
 +<WRAP centeralign>**//Abstract//**</WRAP>
 + \\
 +Clustering data is a challenging problem in unsupervised learning where no gold
 +standard exists. The selection of a clustering method, measures of dissimilarity,
 +parameters, and the determination of the number of reliable groupings, are often viewed
 +as subjective processes. Stability has become a valuable surrogate to performance and
 +robustness that can guide an investigator in selecting and prioritizing clusters. This talk
 +presents a framework for stability measurements based on resampling and out-of-bag
 +estimation. Bootstrapping methods for cluster stability can be prone to overfitting in a
 +setting analogous to poor delineation of test and training sets in supervised learning.
 +Out-of-bag stability, which overcomes this issue, is observed to be consistently more
 +conservative than traditional measures and is uniquely not conditional on a reference
 +clustering. Furthermore, out-of-bag stability estimates can be estimated at different
 +levels: item level, cluster level, and as an overall summary, which has good interpretive
 +value for the investigator. This framework is extended to develop stability estimates for
 +determining the number of clusters (model selection) through contrasts with simulated
 +reference data with no signal. Finally, new out-of-bag stability estimates are developed
 +to address the problems of ensemble clustering and multi-modal clustering. Applications
 +in the Biomedical Sciences are presented. Stability estimation can be implemented
 +using the &quot;bootcluster &quot; package on the Comprehensive R Archive Network (CRAN). 
 + \\
 + 
 +
 +Biography of the speaker: Dr. Hageman Blair is an Associate Professor in Biostatistics
 +at The University at Buffalo. She received her PhD in 2007 in Applied Mathematics from
 +Case Western Reserve University and trained as a post-doc in statistical genetics at
 +The Jackson Laboratory in Bar Harbor, Maine. Her methodological research interests
 +include Computational Biology, Mathematical Biology, Network Theory, Cluster Analysis
 +and Stability. She maintains several collaborations across the Biomedical Sciences and
 +School of Engineering. She serves as the Associate Director of Education in UB’s new
 +Institute of Artificial Intelligence and Data Science, which is home to a PhD program and
 +four interdisciplinary masters programs.
 +
 +</WRAP>