The python code of the
"Star/Quasar Classification ROC Curves" example splits the data set in training and test parts but inside the `compute_results()` function, the whole data set is used for training each classifier.
I am attaching the source code file as downloaded from the link in the webpage (12 Nov 2019).
The fix is trivial: Change line 90 from
model.fit(X_train, y_train)
As a further notice, the resulting ROC plot on the webpage needs to be updated as well due to the changes in the results introduced by the fix.
I was not able to find the source code of that file on the Github repo in order to open an issue there.