The terms false positive and false negative (along with true positive and true negative) come to us from the world of diagnostic tests. An anti-spam product is like a pregnancy test - it eventually comes down to yes or no.
False positive means the test said the message was spam, when in reality it wasn't.
A false negative means that the test said a message was not spam, when in reality it was.
A false negative means that the test said a message was not spam, when in reality it was.
We often think in terms of error rates, but with many diagnostic tests the kind of error is a big deal. It's not enough to know that the test is wrong 29% of the time. We want to know what kind of wrong. Spam tests are exactly like that. A false positive means that good mail might have gotten lost, while a false negative is just annoying. We care more about false positives than we do about false negatives (unless the CEO is getting inundated with false negatives). In addition to wanting to know how many errors there are, we also want to know what type they are.
Source
0 comments:
Post a Comment