I Didn’t See That Coming!

Have two goals: wisdom—that is, knowing and doing right—and common sense. Don’t let them slip away,                                                                                                                                        Proverbs 3:21 (Living Bible)

I was recently reading about Abraham Wald, a Jewish scientist from Hungary who had been  expelled from Nazi Europe in World War II. As we have seen often, when political thinking gets involved in science, foolish decisions are often made. Indeed, Wald played a part in helping to defeat Nazi Germany with his mathematical prowess and brilliant logic. The irony, played out more than once in World War II, is that brilliant scientists expelled from Nazi Germany because of their Jewish heritage, helped to defeat that same evil power.

Wald was tasked to solve the problem of finding the most vulnerable parts of Allied bombers so that more armor could be added to protect planes and crews. The placement of armor had to be strategic, since armor was heavy, and planes needed to be as light as possible.

Wald was given access to information about where returning bombers had sustained the most enemy damage during their bombing runs. He saw where most of the damage occurred, and he surprisingly suggested that armor be placed mostly in the areas where the most damage had not been sustained.  

He explained that they were studying planes whose damage, while at times extensive, had allowed them to return safely. The planes which were hit in the areas other than these spots had not been able to return home. The concept he formulated was “survivorship bias”, meaning that all factors needed to be included in the analysis, not just the damage to the surviving aircraft. The planes that had not survived also needed to be in the equation.

I found the solution to be fascinating, and at the same time, almost obvious- an idea that we might easily overlook. We often have unknown biases when we study problems. Wald had the insight and logic to utilize this concept to save many bomber crews.

What appears to be clear to us, can also be missed because of hidden bias. Information that we do not consider might be the most important things in the equation.

Prayer: Thank you for the gifts that you give to us, especially the ones we do not see, Amen