I like the BBC article on the birthday paradox overall, but am a little upset at their math. Fletcher correctly states the birthday paradox in the bold intro text and later in the article, but blatantly gets it wrong in the hypothetical story involving Hulk and Paulinho at the beginning of the article. The whole point (in a sense) of the birthday paradox is that it only works if you _don’t_ specify two people. As soon as you narrow down your probability space to two particular players chatting in their hotel, the odds of them sharing a birthday is back down to ~1/365.
Grrr. I know I’m preaching to the choir here, but wanted to vent. Anyway, it’s very cool that the mathematical prediction so nicely pans out with WC teams!

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