Statistics for bioinformatics. Filtering microarray data. Aims of filtering. Suppose We have a set of 10000 genes whose expression is measured on our microarray chips. We are looking at an experiment where gene expression is measured in 11 cancer patients and 7 normal individuals.
Statistics for bioinformatics
Filtering microarray data
- Z is N(0,1)
has a limiting distribution ( ) which is normal with mean 0 and variance 1, where
parameters m and n.
where is N(0,1) and is
[S is the sample standard deviation]
with n-1 degrees of freedom”.
Are the sample means different?
The significance of the difference in means depends on the variances.
H0: bj=0 for all j
and proceed in a similar manner (although with different components of variance in the F-statistic) to before.
Mean 10 4
Group 1 Group 2
[References for more info on statistics, esp. statistical tests: Introduction to mathematical statistics by Hogg & Craig (Maxwell Macmillan); http://davidmlane.com/hyperstat/index.html ]