Question about FC/ ratio
1
0
Entering edit mode
5.0 years ago
kanwarjag ★ 1.2k

I have to clarify another step from my previous question @ log ratio in gene expression array

If two values are A-32 B -18 If I have to present data as FC and log FC For FC it will be 32-18= 1.7 this will be a linear FC

and log FC= LogA-logB will be 5-4.1=1.19= 0.2 when we use log values of A and B, Do we again shift the results to log value- log 1.19

Or we present logFC as log of linear FC- meaning log (1.7)= 0.8 What is the best and correct way of presentation.

expression • 1.2k views
ADD COMMENT
0
Entering edit mode
5.0 years ago
JC 13k

The math for those are:

A = 32 -> log(A) = 1.50514997832
B = 18 -> log(B) = 1.2552725051

FC(AB) = A / B = 32 / 18 = 1.77777777778 -> log(FC) = log(1.77777777778) = 0.24987747321

logFC(AB) = log( A / B) = log(A) - log(B) = 1.50514997832 - 1.2552725051 = 0.24987747322
ADD COMMENT
0
Entering edit mode

Thanks. So RamsRS has suggested "And if your numbers are starting off in log space (since you have A - B depicting a ratio), then C is already a log value and does not need to transform to log space". @ log ratio in gene expression array I want to clarify this issue; so one has not to transform log C also. that was the confusion.

ADD REPLY

Login before adding your answer.

Traffic: 1266 users visited in the last hour
Help About
FAQ
Access RSS
API
Stats

Use of this site constitutes acceptance of our User Agreement and Privacy Policy.

Powered by the version 2.3.6