alt Hacker News> Same AI in “real life” would score probably much better eventually
Either I don't understand your reasoning or you are very much wrong. A "real life" dataset would contain real negatives too and the result would be equal if false positive rate was zero and strictly worse if the rate was any higher. One should expect the same AI to score significantly worse in a real life setting.
Depends on what you call better or worse. In real life positives (TN) are far less common than negatives (TN), if this system does not have lots of FP (which is very possible), the accuracy will be much better than you may expect.
What I mean with “score” is having a relatively high accuracy.
Come let’s do the math: incidence of BC is 1 every 12, lets say. Now let’s say we have 12000 patients:
Acuracy = (TP + TN) / (TP + TN + FP + FN) = (1000 + 11000) / (1000 + 11000 + 300 + 0) = 12000 / 12300 =0.976 the test is 97.6% accurate… pretty impressive huh?
Tell me if I’m wrong. Is a know fact that you have to be careful when doctor speak of % accuracy.