Barsalou then goes all math geek and applies to the data the Bayes’ Theorem formula for calculating conditional probabilities. After a little mathematical shake and bake, he determines there is a 61.9 percent chance that any given casualty is wearing a red shirt. That still sounds high, but it’s not really once you consider the sheer number of redshirts running around the Starship.
“Although Enterprise crew members in redshirts suffer many more casualties than crew members in other uniforms, they suffer fewer casualties than crew members in gold uniforms when the entire population size is considered,” Barsalou writes. “Only 10 percent of the entire redshirt population was lost during the three year run of Star Trek. This is less than the 13.4 percent of goldshirts, but more than the 5.1 percent of blueshirts.” –Surprise! 'Star Trek' gold shirts more deadly than red shirts – CNET Mobile.