suggested addition

Manu58 · Manu58 · commit e8d696e6690f · 2015-03-14T17:16:22.000+01:00
diff --git a/statinf.md b/statinf.md
@@ -3,3 +3,5 @@ layout: page
 title: Statistical Inference
 permalink: /statinf/
 ---
+
+- [Why degrees of freedom decrease for sample variance](https://github.com/Manu58/bias/blob/master/bias.pdf)
