Realistic (Math 1)

What’s the chance that a po­ten­tially good part­ner would flake on the first date?

From a test sub­ject for an early ver­sion of the Bayes in­tro:

A 96% OKCupid match can­celed their first date for coffee with­out pro­vid­ing an ex­pla­na­tion.

She es­ti­mated that a man like this one had prior odds of 2 : 5 for de­sir­a­bil­ity vs. un­de­sir­a­bil­ity, based on his OKCupid pro­file and her past ex­pe­rience with 96% matches. She then es­ti­mated a 1 : 3 like­li­hood ra­tio for de­sir­able vs. un­de­sir­able men flak­ing on the first date. This worked out to 2 : 15 pos­te­rior odds for the man be­ing un­de­sir­able, which she de­cided was un­fa­vor­able enough to not pur­sue him fur­ther.

She used this ex­plic­itly Bayesian calcu­la­tion to in­ter­rupt a ‘wor­ry­ing’ cy­cle wherein she was fo­cus­ing on one con­sid­er­a­tion, then a differ­ent con­sid­er­a­tion, ar­gu­ing for pur­su­ing fur­ther /​ not pur­su­ing fur­ther. Mak­ing up num­bers and do­ing the Bayesian calcu­la­tion ter­mi­nated this cy­cle.