DOC Fix typo: x axis -> y axis
@@ -409,7 +409,7 @@ def precision_recall_curve(y_true, probas_pred, pos_label=None,
The last precision and recall values are 1. and 0. respectively and do not
have a corresponding threshold. This ensures that the graph starts on the
- x axis.
+ y axis.
Read more in the :ref:`User Guide <precision_recall_f_measure_metrics>`.
