Google Analystics

Thursday, 7 March 2019

Survivorship Bias

Published by David McRaney  in 2013, I found this article, Survivorship Bias, on the web while looking for information on a brilliant stats-mathematician by the name of Abraham Wald.

A five to ten minute read, I found the article fascinating with lots of food for thought - challenging what often appears axiomatic. To illustrate a point about survivorship bias, Wald comes into the picture because he was called upon to help determine where additional armour should be placed to increase the chances of WW II British and American bombers and their crews making it back to base after a bombing mission - missions that always included running the gauntlet of heavy anti-aircraft artillery and the consequent heavy loss of aircraft and life. The military examined planes that returned and documented where the most damage was. It looked like this:



Military commanders wanted to put the thicker protection where they could clearly see the most damage, where the holes clustered. Were they right? No. Read the article to find out why - and why it's time to review many of your obviously correct assumptions about so many things.

Survivorship Bias by David McRaney