This is a test version of Biostars. For the public version, visit https://www.biostars.org.
Convert Fdr Control Q-Value To P-Value

Hi everyone,

I have downloaded a set of processed data of gene expression relationship, while they offered a result of q value. Since I want to use the p value to adjust the next step, how can I convert this Q value to p value?

Thanks!

• 6,964 views • link
updated by admiral.david • admiral.david • written by J.F.Jiang J.F.Jiang

Is it possible that your dataset was analyzed by a method that does not produce p-values? For example, baySeq, a tool for testing differential expression in RNA-Seq data, produces posterior probabilities from a Bayesian analysis and calculates FDR directly from them. The nature of the calculations is such that no p-value is involved.

• 0 views • link
written by Ryan Thompson Ryan Thompson

How did you get your Q values ?

• 0 views • link
written by ff.cc.cc ff.cc.cc

1 answer

I think the short answer is that you can't. One way to calculate a Q value estimate is from a distribution of P values (e.g. the way Storey's qvalue works), but I don't think there is any way to reconstruct the P value distribution from a set of estimated Q values. You should calculating the P values directly if that's what you want. The manual to the qvalue package has more information about what a Q value is and how it can be calculated, which you might want to read.

• 0 views • link
written by David Quigley David Quigley

YES, I have read the wiki of Q value and methods of original author, I can not convert this Q, but I can still estimate the p-value

• 0 views • link
written by J.F.Jiang J.F.Jiang

Log in to answer this question.

More posts like this