Statistics and Data Analysis for Microarrays Using R and Bioconductor, 2nd Edition

Chapter 16

Multiple comparisons

Quantitative accumulations lead to qualitative changes.

—Karl Marx

16.1 Introduction

The problem of multiple comparisons is probably the most challenging to pic

for the typical life sc ie ntist. We will introduce this problem through an ex-

ample that illustrates the dangers that lurk behind multiple comparisons. We

will then approach the problem from a statistical perspective and prove that

multiple comparisons need to be treated in a special way. Once this is clear,

the chapter will present a few classical solutions to the problem as well as the

best choices from a microarray data analysis perspective.

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