Robust estimation and hypothesis testing in microarray analysis

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2010

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Ülgen, Burçin Emre

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Microarray technology allows the simultaneous measurement of thousands of gene expressions simultaneously. As a result of this, many statistical methods emerged for identifying differentially expressed genes. Kerr et al. (2001) proposed analysis of variance (ANOVA) procedure for the analysis of gene expression data. Their estimators are based on the assumption of normality, however the parameter estimates and residuals from this analysis are notably heavier-tailed than normal as they commented. Since non-normality complicates the data analysis and results in inefficient estimators, it is very important to develop statistical procedures which are efficient and robust. For this reason, in this work, we use Modified Maximum Likelihood (MML) and Adaptive Maximum Likelihood estimation method (Tiku and Suresh, 1992) and show that MML and AMML estimators are more efficient and robust. In our study we compared MML and AMML method with widely used statistical analysis methods via simulations and real microarray data sets.

Subject Keywords

Robust statistics., Estimation theory.

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http://etd.lib.metu.edu.tr/upload/12612352/index.pdf
https://hdl.handle.net/11511/20026

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. E. Ülgen, “Robust estimation and hypothesis testing in microarray analysis,” Ph.D. - Doctoral Program, Middle East Technical University, 2010.