Twenty-three of us were selected to join the Bachelor of Statistics course at the Indian Statistical Institute (ISI), Kolkata. There were only two female students in our class. One day our statistics teacher asked us to write down on a sheet of paper the number of brothers and sisters, including ourselves, that each of us had. On that day, both our female classmates were absent. We added up the numbers and found that there were a total of 68 children in our 21 families, which meant that on an average each of us had 3.23 siblings. Looked reasonable.

Of the 68, 45 were male and 23 were female. These numbers were odd. One expects roughly equal numbers of male and female children in a set of families. But, in this set of families, the number of male children vastly outnumbered female children. During World War II, the Allied Forces were losing many bombers to enemy anti-aircraft fire. The U.S. military wanted to reduce the number of losses and wanted to approach these military problems using research methodology. Therefore, they established a Statistical Research Group (SRG) in Columbia University in 1942, comprising 18 researchers from various domains of science, primarily mathematicians, statisticians and economists. Many of the planes that returned from combat had taken bullet hits.

The researchers mapped the bullet holes and found that most had received bullets to the wings and tail. The engine was spared. The U.S. military concluded that it was necessary to reinforce the wing and tail areas with armour, because these areas were taking the most fire and therefore that’s where they needed more protection. Wrapping an entire aircraft with armour was not an option because it would make the aircraft too heavy, and therefore too sluggish during flight. However, one member of the SRG provided an argument that was counter-intuitive and counter to the U.S. military’s conclusion. He said that areas that were least damaged on the returning planes needed the most protection, not the areas in which hits were concentrated.

We celebrate that SRG member’s birthday on 31 October. His name........

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