Using credibility intervals instead of hypothesis tests in SAGE analysis.

Ricardo Z N Vêncio; Helena Brentani; Carlos A B Pereira

doi:10.1093/bioinformatics/btg357

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Using credibility intervals instead of hypothesis tests in SAGE analysis.

Ricardo Z N Vêncio·Helena Brentani·Carlos A B Pereira

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Abstract

MOTIVATION: Statistical methods usually used to perform Serial Analysis of Gene Expression (SAGE) analysis are based on hypothesis testing. They answer the biologist's question: 'what are the genes with differential expression greater than r with P-value smaller than P?'. Another useful and not yet explored question is: 'what is the uncertainty in differential expression ratio of a gene?'. RESULTS: We have used Bayesian model for SAGE differential gene expression ratios as a more informative alternative to hypothesis tests since it provides credibility intervals. AVAILABILITY: The model is implemented in R statistical language script and is available under GNU/GLP copyleft at supplemental web site. SUPPLEMENTARY INFORMATION: http://www.ime.usp.br/~rvencio/SAGEci/

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Algorithms Breast Neoplasms Expressed Sequence Tags Gene Expression Profiling Humans Models, Genetic Models, Statistical Reproducibility of Results Sensitivity and Specificity Sequence Analysis, DNA Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Validation Study

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Ricardo Z N Vêncio, Helena Brentani, Carlos A B Pereira. 2003-12-12. Using credibility intervals instead of hypothesis tests in SAGE analysis.. https://doi.org/10.1093/bioinformatics%2Fbtg357

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