DOC Adds missing B to the denominator in model_evaluation
@@ -939,7 +939,7 @@ To make this more explicit, consider the following notation:
* :math:`y_l` the subset of :math:`y` with label :math:`l`
* similarly, :math:`\hat{y}_s` and :math:`\hat{y}_l` are subsets of
:math:`\hat{y}`
-* :math:`P(A, B) := \frac{\left| A \cap B \right|}{\left|\right|}` for some
+* :math:`P(A, B) := \frac{\left| A \cap B \right|}{\left|B\right|}` for some
sets :math:`A` and :math:`B`
* :math:`R(A, B) := \frac{\left| A \cap B \right|}{\left|A\right|}`
(Conventions vary on handling :math:`B = \emptyset`; this implementation uses
