I seem to manage to make it work by adding two additional lines at the beginning to enforce input y_train / y_val to be panda df, with the same index from corresponding X_train / X_val
y_train = pd.DataFrame(y_train, index = X_train.index)
y_val = pd.DataFrame(y_val, index = X_val.index)
After this, I can successfully generate y_treat/control_train/val, using example here
y_treat_train = y_train.loc[X_treat_train.index]
This way, it works for unit test which uses array as input for y_train/val, and also works for later cell which uses df as input.
However, the autograder is still failing
I’d appreciate if someone could look into this myterious bug.
Thanks
Huan