DOC Wording in crossval example (#10820)

gamazeps · jnothman · commit 19e2772cac4a · 2018-03-18T09:30:11.000+11:00
Replace "Luck" by "Chance" on the crossvalidation example as it
sounds better in English.
diff --git a/examples/model_selection/plot_roc_crossval.py b/examples/model_selection/plot_roc_crossval.py
@@ -80,7 +80,7 @@
 
     i += 1
 plt.plot([0, 1], [0, 1], linestyle='--', lw=2, color='r',
-         label='Luck', alpha=.8)
+         label='Chance', alpha=.8)
 
 mean_tpr = np.mean(tprs, axis=0)
 mean_tpr[-1] = 1.0
