JAFROC figure of merit vs. area under fitted AFROC curve. The area under the fitted AFROC or wAFROC curve is currently not used as a figure of merit. There are benefits to using it, but further research is needed. The JAFROC figure of merit uses the raw data and calculates a Wilcoxon-like statistic. For further details see: Chakraborty DP, Zhai X. On the meaning of the weighted alternative free-response operating characteristic figure of merit. Medical physics. 2016;43(5):2548-2557. This paper explains the calculation at a basic level.