I'm using a confusion matrix and the metrics that we can derived from that (sensitivity, specificity etc).
I've calculated the False Negative Rate (FN/TN+FN) and I'm in a big discussion with my colleague who thinks that the FN/(TN+FN+TP+FP) is more relevant and representative.
I couldn't find this formula in the literature. Is it something wrong? Could that lead to fallacy? Any argument against or for it?
Thank you for your help!