BOPA : a bayesian hierarchical model for outlier expression detection

DNA microarray technologies have the capability of simultaneously measuring the abundance of thousands of gene expressions in cells. A common task with microarrays is to determine which genes are differentially expressed under two different biological conditions of interest (e.g. cancerous against n...

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Bibliographic Details
Main Author: Hong, Zhaoping
Other Authors: Lian Heng
Format: Thesis
Language:English
Published: 2012
Subjects:
Online Access:https://hdl.handle.net/10356/49053
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author Hong, Zhaoping
author2 Lian Heng
author_facet Lian Heng
Hong, Zhaoping
author_sort Hong, Zhaoping
collection NTU
description DNA microarray technologies have the capability of simultaneously measuring the abundance of thousands of gene expressions in cells. A common task with microarrays is to determine which genes are differentially expressed under two different biological conditions of interest (e.g. cancerous against non-cancerous cells). It is often the case that there are thousands of genes for a single individual but relatively few individuals in the data set. Additionally, in many cancer studies, a gene may be expressed in some but not all of the disease samples, reflecting the complexity of the underlying disease. Traditional t-tests assume a mean shift for the tumor samples compared to normal samples and is thus not structured to capture partial differential expression. More powerful tests specially designed for this situation are needed to find genes with heterogeneous expressions associated with possible subtypes of the cancer. This thesis proposes a Bayesian model for cancer outlier profile analysis (BOPA). We build on the Gamma-Gamma model introduced in Newton et al. (2001); Kendziorski et al. (2003) and Newton et al. (2004), by using a five-component mixture model to represent various differential expression patterns. The hierarchical mixture model explicitly accounts for outlier expressions and inferences are based on samples from posterior distributions generated from a Markov chain Monte Carlo algorithm. We present simulation and real-life datasets analysis to demonstrate our proposed methodology.
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spelling ntu-10356/490532023-02-28T23:48:21Z BOPA : a bayesian hierarchical model for outlier expression detection Hong, Zhaoping Lian Heng School of Physical and Mathematical Sciences DRNTU::Science::Mathematics::Statistics DNA microarray technologies have the capability of simultaneously measuring the abundance of thousands of gene expressions in cells. A common task with microarrays is to determine which genes are differentially expressed under two different biological conditions of interest (e.g. cancerous against non-cancerous cells). It is often the case that there are thousands of genes for a single individual but relatively few individuals in the data set. Additionally, in many cancer studies, a gene may be expressed in some but not all of the disease samples, reflecting the complexity of the underlying disease. Traditional t-tests assume a mean shift for the tumor samples compared to normal samples and is thus not structured to capture partial differential expression. More powerful tests specially designed for this situation are needed to find genes with heterogeneous expressions associated with possible subtypes of the cancer. This thesis proposes a Bayesian model for cancer outlier profile analysis (BOPA). We build on the Gamma-Gamma model introduced in Newton et al. (2001); Kendziorski et al. (2003) and Newton et al. (2004), by using a five-component mixture model to represent various differential expression patterns. The hierarchical mixture model explicitly accounts for outlier expressions and inferences are based on samples from posterior distributions generated from a Markov chain Monte Carlo algorithm. We present simulation and real-life datasets analysis to demonstrate our proposed methodology. DOCTOR OF PHILOSOPHY (SPMS) 2012-05-14T06:25:02Z 2012-05-14T06:25:02Z 2012 2012 Thesis Hong, Z. P. (2012). BOPA : a bayesian hierarchical model for outlier expression detection. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/49053 10.32657/10356/49053 en 113 p. application/pdf
spellingShingle DRNTU::Science::Mathematics::Statistics
Hong, Zhaoping
BOPA : a bayesian hierarchical model for outlier expression detection
title BOPA : a bayesian hierarchical model for outlier expression detection
title_full BOPA : a bayesian hierarchical model for outlier expression detection
title_fullStr BOPA : a bayesian hierarchical model for outlier expression detection
title_full_unstemmed BOPA : a bayesian hierarchical model for outlier expression detection
title_short BOPA : a bayesian hierarchical model for outlier expression detection
title_sort bopa a bayesian hierarchical model for outlier expression detection
topic DRNTU::Science::Mathematics::Statistics
url https://hdl.handle.net/10356/49053
work_keys_str_mv AT hongzhaoping bopaabayesianhierarchicalmodelforoutlierexpressiondetection