Still random after all these years?
When Philip Humber of the Chicago White Sox pitched a perfect game against the Seattle Mariners back in April, I wrote that the frequency of these exceedingly rare feats had ramped up dramatically over the last three decades. Mathematicians argued that speedup was more apparent than real, a classic example of a Poisson distribution. This is the natural tendency for exceptionally rare but random events to bunch up in ways that appear non-random. Humber's flawless game was the 19th in modern baseball's 112-year* history. Since April, there have been two more, including the 1-0 gem Félix Hernández of the Seattle Mariners pitched against the Tampa Bay Rays...