I would like to remind you of two seminars presented by our Snedecor
Lecturer, Jianqing Fan of Princeton University. Professor Fan will speak
this afternoon at 4:10 in 319 Snedecor on "Statistical Challenges with High
Dimensionality in Feature Selection." He will give a second lecture
Tuesday morning at 11:00 in Atanasoff B29 entitled "Exploiting sparsity and
within-array replications in analysis of microarray data." The abstract
for this second talk appears below.
Abstract
Normalization of microarray data is essential for coping with
experimental variations and revealing meaningful biological results.
We have developed a normalization procedure based on Semi-Linear
In-slide Model (SLIM), which adjusts objectively experimental
variations and are applicable to both cDNA microarrays and
Affymetrix oligonucleotide arrays. We then present methods for
validating the effectiveness of different methods of normalization,
using within-array replications. We exploit the sparsity in
differently expressed genes for normalization and analysis of gene
expressions. The significant analysis of gene expressions is based
on a variation t-statistic. The P-values are estimated based on
a
sieved permutation, which explores the sparsity of differently
expressed genes. The use of the newly developed techniques is
illustrated in a comparison of the expression profiles of
neuroblastoma cells that were suppressed by a growth factor,
macrophage migration inhibitory factor.
Dan Nettleton
Associate Professor
Department of Statistics
Iowa State University