Monthly Archives: February 2009

I know plenty of economists who are fond of Guinness, but not many who realise just how important the beer has been to the profession. The man who laid the foundations for the global success of Guinness also produced one of the most important tools in economics – and a tool that is widely mishandled today.

Faced with an apparent pattern in any data, a key question is always: “Does this pattern represent something real, or is it just chance?” The simplest example: if I measure the heights of five men and five women and discover that the men tend to be taller than the women, I might be on to something, or I might just have some tall men and some short women in my sample. Based on this small sample, how confident should I be that men are in general taller than women?

The statistical apparatus to check this is a test called Student’s t-test. Student was the pseudonym of William Sealy Gosset, an amiable, rucksack-wearing chemist who – beginning in 1899 – worked all his adult life for Guinness and eventually rose to the rank of head brewer. So nervous was the company about commercial confidentiality that Gosset published surreptitiously under his pseudonym.

The remainder of the article can be read here. please post comments below.

The Undercover Economist: a guide

Publishing schedule: Excerpts from "The Undercover Economist" and "Dear Economist", Tim's weekly columns for the FT Magazine, are published on this blog on Saturday mornings.
More about Tim: Tim also writes editorials for the FT, presents Radio 4's More or Less and is the author of "The Undercover Economist" and "The Logic of Life".
Comment: To comment, please register with FT.com, which you can do for free here. Please also read our comments policy here.
Contact: Tim's contact address is: economist@ft.com
Time: UK time is shown on posts.
Follow: A link to the blog's RSS feeds is at the top of the page.
Follow on Twitter
FT blogs: See the full range of the FT's blogs here.