Update week9.do.txt

doc/src/week9/week9.do.txt

@@ -2,6 +2,7 @@ TITLE: Week 11, March 11-15: Resampling Techniques, Bootstrap and Blocking
 AUTHOR: Morten Hjorth-Jensen {copyright, 1999-present|CC BY-NC} Email [email protected] at Department of Physics and Center fo Computing in Science Education, University of Oslo, Oslo, Norway & Department of Physics and Astronomy and Facility for Rare Ion Beams, Michigan State University, East Lansing, Michigan, USA
 DATE: March 11-15
 
+# To do: improve blocking part, better derivation
 
 !split
 ===== Overview of week 11, March 11-15 =====