In am trying to use some sort of Venn diagram in order to give a visual interpretation for a particular point in a ROC curve space. This made me think that it might be good to build a tool to explore the ROC space using Venn diagrams for the visual interpretation of the information in the confusion matrix.
Here is an example: The Venn diagram at the top right allows to modify the test (T) and condition (C) sets, which describe a single point in the ROC space. Then by modifying these relations (for instance displacing T over C) the ROC curve gets displayed.
However using displacement alone produces a line, since the True Positive Rate (TPR) and False Positive Rate (FPR) grow and shrink at the same rate. Therefore in order to produce ROC curves TPR and FPR need to grow at differently, so the circles should change.
Do you think that a tool like this, would be useful to understand the ROC curve space? How would you construct the tool?