ROC analysis, CAFA 2 experiment
The paper doesn't seem to have been written for general readers. Unfortunately I don't understand the equations enough to be able to explain what the categorical and continuous variables are. Just in case it helps, here are the equations from the paper showing the precision/recall calculations:

$$\begin{array}{@{}rcl@{}} \text{pr}(\tau) &amp;=&amp; \frac{1}{m(\tau)}\sum\limits_{i=1}^{m(\tau)} \frac{{\sum\nolimits}_{f} \unicode{x1D7D9}\left(f \in P_{i}(\tau) \wedge f \in T_{i}\right)}{\sum_{f} \unicode{x1D7D9}\left(f \in P_{i}(\tau) \right)},\\ \text{rc}(\tau) &amp;=&amp; \frac{1}{n_{e}}\sum\limits_{i=1}^{n_{e}} \frac{{\sum\nolimits}_{f} \unicode{x1D7D9}\left(f \in {P}_{i}(\tau) \wedge f \in T_{i}\right)}{{\sum\nolimits}_{f} \unicode{x1D7D9}\left(f \in T_{i} \right)}, \\ F_{\max} &amp;=&amp; \max_{\tau} \left\{ \frac{2\cdot \text{pr}(\tau)\cdot \text{rc}(\tau)}{\text{pr}(\tau) + \text{rc}(\tau)} \right\}, \end{array} $$


  where P i (τ) denotes the set of terms that have predicted scores greater than or equal to τ for a protein sequence i, T i denotes the corresponding ground-truth set of terms for that sequence, m(τ) is the number of sequences with at least one predicted score greater than or equal to τ, $\unicode{x1D7D9}\left (\cdot \right)$ is an indicator function, and n e is the number of targets used in a particular mode of evaluation.