minor rewording

diff --git a/README b/README
index e415c42..fa2f6b6 100644
--- a/README
+++ b/README
@@ -608,7 +608,7 @@ The 'overlap score' is computed in the following way:

         +1,	when RACS detects a region and MACS2 does not
         -1,	when MACS2 detects a region and RACS does not
-        ratio of region sizes,	when there is an overlap between the regions determined by RACS and MACS2
+        ratio between region sizes,	when there is an overlap between the regions determined by RACS and MACS2

 Utilizing these overlap scores, then one could visualize this comparison using
 the following function: