I have an application that basically circles things in images. I need to find the false positive rate. Wikipedia says it's given by (number of False Positives) / (number of False Positives + number of True Negatives).
I don't have a true negative count, and I'm not sure it means anything here, since the application does not explicitly say no.
All I really have to work with are the number of items it was supposed to circle, the number of those it actually circled, and the number of false positives.
Is there anything I can do with this data to get some sort of useful false positive percentage?