Data Adjustment: Percentage Cutoff
Parameter Information
Overview of Percentage Cutoff
The Percentage Cutoff data adjustment acts as a filter to remove genes
that have fewer than some percentage of valid values for the experiments under
study. It is common in microarray expression analysis to have some missing data,
however, if a particular gene has fewer than some percentage of it's values then the
gene can not be reliably compared to other genes.
This filtering method permits the
you to select a criteria such that any gene having fewer good values than the supplied
percentage will be removed from analyis runs. The history log will report the number
of genes that are remaining after the cuttof is applied using the "use percent cutoff"
menu option to enforce the cutoff.
Cutoff Parameter
This value, ranging from 0.0% to 100.0%, represents the percentage of valid
values that a gene is required to have in order to be allowed into analysis
algorithms. (e.g. 10 experiments loaded, cutoff criteria is 75%, if a gene
has only 6 valid values (60%) then that gene is not a candidate for analysis
while a gene having 8 valid values (80%) would be accepted.)