In today's Email Insider column, "Statistics, Lies, and Mathematical Literacy", I wrote about some of the common errors that I see in email marketing on a regular basis with regard to the use of statistics. Honestly, it scares me a little when different statistical terms are used incorrectly. It concerns me greatly when clearly bad statistics about email marketing or direct marketing are published and not widely scrutinized.

I believe we could brush up a little. Not convinced?  Well try a few basic questions and see how you do:

1) What is the difference between "average" and "mean"? Mean and median? Median and mode?
2) Assuming a normal distribution, what percentage of cases fall within 1 standard deviation? Within 2 standard deviations?
3) What is a null hypothesis?
4) What is the name of the test for identifying significant differences?

I consider myself a "stats guy", having taken a lot of statistics both as an undergrad and in grad school. Even so, I am not embarrassed to say that the reference book used most often in my office is an old statistics textbook I bought at a used bookstore for $5.

Something similar, in combination with the book I wrote about in the article, "How to Lie with Statistics" should help you discern--and question when appropriate--the next time you hear something about averages and "significant" findings.