i-TFTD #296: Dead Evidence

This is an interesting snippet from a short piece at BusinessPundit.com written by Rob May in July 2007 titled
What Bullet Holes in Airplanes Can Teach You About Making Better Business Decisions

During World War II, statistician Abraham Wald tried to determine where to add extra armor to airplanes. Based on the patterns of bullet holes in returning airplanes, he suggested that the parts not hit should be protected with extra armor. Why?

Wald was looking at what is sometimes called "dead evidence." He reasoned like this... if these planes are returning, we know that if they are hit in the spots they have been hit, they can still fly. The planes that did not return must have been hit in different places. So put the extra armor wherever the returning planes were not hit.

I think most people would have a natural inclination to put the armor where the returning planes had been hit. The real answer is simple, but counterintuitive. It's called "dead evidence" because it is what people ignore when they make these judgments.

(Thanks to Ramanan Jagannathan for sharing this.)

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Many creative thinking techniques involve consciously inverting our view, looking at the opposite of the normal, imagining upside down and inside out. Could be applied in any situation where we want to get new ideas and insights.
Examples:
-Attrition is a concern in any company, instead of only looking at exit interviews to analyze why leavers are leaving, find out why stayers are staying and strengthen those attributes in the company
-Everyone seems to be buying a brand or investing in some asset, instead of finding reasons for that, analyze the reasons why others are not buying that.