Why variances add - and why it matters.

Book: 
Thinking and reasoning with data and chance: Sixty-eighth Yearbook.
Authors: 
Bock, D., & Velleman, P. F.
Editors: 
Burrill, G. F.
Type: 
Chapter
Category: 
Teaching
Pages: 
377-390
Year: 
2006
Publisher: 
National Council of Teachers of Mathematics. Reston, VA.
Abstract: 

We present examples in which the addition of variances is key to gaining insight when dealing with binomial probabilities, inference and the central limit theorem.

The CAUSE Research Group is supported in part by a member initiative grant from the American Statistical Association’s Section on Statistics and Data Science Education