I'm working on a example understanding Bayes, and wondering if my thought process is correct. So I have three users, and true or false if they own Nike or Reebok shoes, or both. I want to calculate the probability of Reebok's if they own Nike's. Here is my data:
User | Nike | Reebok Jesse | true | false Jake | false | true John | true | true - only user with both
Here is how I'm attempting to do this:
1) P(both/just Reebok) = 1/2 = 50%
2) P((total user with either - both)/total user with either = (3-1)/3 = 67% 3) Normalize P = 50%/(50%+67%) = 43%
So the result would be if a user owned Nike's, they have a 43% probability of owning Reebok's.