Hello, I have a question on FDR. Guidelines recommend to use FDR when running multiple hypothesis to remove chances of false positives. However, I can not find a reference indicating what is cutoff to start using FDR? Something such, "when running than XX comparisons, use FDR".

Anybody could help?

Thank you!!!

# include your problematic code here with any corresponding output 
# please also include the results of running the following in an R session 

sessionInfo( )

You chose your cutoff based on the rate of false positives desired among the returned set of genes. Consult papers perhaps to get an idea of what thresholds are used. 5% and 10% are common in discovery-driven genomics projects.