The Flaw of Averages: Why We Underestimate Risk in the Face of Uncertainty

CHAPTER 34

Cawlfield’s Principle

Anyone who has seriously mastered Microsoft Excel will understand why I refer to this skill as a folk art, passed down in the oral tradition. I joke in my classes about learning Excel secrets from a master craftsman in the hills of Tennessee. When I met David Cawlfield in 2006, it was soon clear that he was in fact such a master. David is principal engineer at Olin Chemical’s Chlor-Alkali Division and works at their plant in Charleston, Tennessee. They produce inorganic chemicals such as chlorine, caustic soda, bleach, and other things that you don’t want to touch but that we can’t live without.

From Remedial Math to Chemical Engineer

When David was in fifth grade, he found multiplication tables particularly boring. Thus his teachers determined he was bad at math and should be put into a remedial program. Luckily his father, a math editor for a major publisher, knew a thing or two about math education himself. David’s parents quickly taught him multiplication using flash cards and then convinced his teachers to put him into the advanced math program instead of the remedial one. No longer bored, David flourished. He went on to become a chemical engineer, but his activities at Olin have taken him as far afield as mathematical optimization, computer control systems, and, of course, Microsoft Excel.

A Problem at Olin

Recently David grappled with an ongoing problem at a chemical production facility. The plant had enough capacity to fill 110 percent ...