diff --git a/doc/src/sgml/acronyms.sgml b/doc/src/sgml/acronyms.sgml
index 2df6559acc..a60ff54a6c 100644
--- a/doc/src/sgml/acronyms.sgml
+++ b/doc/src/sgml/acronyms.sgml
@@ -408,6 +408,26 @@
+
+ MCF
+
+
+ Most Common Frequency, that is the frequency associated with some
+ Most Common Value
+
+
+
+
+
+ MCV
+
+
+ Most Common Value, one of the values appearing most often within a
+ particular table column
+
+
+
+
MITM
diff --git a/doc/src/sgml/planstats.sgml b/doc/src/sgml/planstats.sgml
index df85ea5eea..d2b84b301f 100644
--- a/doc/src/sgml/planstats.sgml
+++ b/doc/src/sgml/planstats.sgml
@@ -203,7 +203,7 @@ EXPLAIN SELECT * FROM tenk1 WHERE stringu1 = 'xxx';
MCVs:
-selectivity = (1 - sum(mvf))/(num_distinct - num_mcv)
+selectivity = (1 - sum(mcv_freqs))/(num_distinct - num_mcv)
= (1 - (0.00333333 + 0.003 + 0.003 + 0.003 + 0.003 + 0.003 +
0.003 + 0.003 + 0.003 + 0.003))/(676 - 10)
= 0.0014559