Make clear which variance is which.

haskell · Sep 14, 2009 · 74cfaa1 · 74cfaa1
1 parent 9e7e4c6
commit 74cfaa1
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/Statistics/Sample.hs b/Statistics/Sample.hs
@@ -132,15 +132,17 @@ robustVar samp = fini . foldlU go (V 0 0) $ samp
     n            = lengthU samp
     m            = mean samp
 
--- | Maximum likelihood estimate of a sample's variance.
+-- | Maximum likelihood estimate of a sample's variance.  Also known
+-- as the population variance.
 variance :: Sample -> Double
 variance = fini . robustVar
   where fini (T v n)
           | n > 1     = v / fromIntegral n
           | otherwise = 0
 {-# INLINE variance #-}
 
--- | Unbiased estimate of a sample's variance.
+-- | Unbiased estimate of a sample's variance.  Also known as the
+-- sample variance.
 varianceUnbiased :: Sample -> Double
 varianceUnbiased = fini . robustVar
   where fini (T v n)