mean fluorescence intensity, ratio - (Dec/31/2012 )

I am confused in flow data analysis, Can someone explain me what ratio of MFI show us. meaning GFP/RFP ratio.
Thanks

leyshmanioz on Tue Jan 1 04:11:57 2013 said:

can you give us some more information, such as what did you tag with GFP or RFP ?
Generally speaking, you can compare levels of expression with the MFI ratio.

The cells express both GFP and RFP, but RFP has to be silenced, since we see double positive population we look at MFI to see the tendency. I'm not sure how can this ratio be interpreted