Machine Learning - Map same line of training data to multiple targets

Question

Let me start by saying that I am total noob when it comes to Machine Learning, so please excuse me if this is a stupid question.

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I was making a MultinomialNB model following this tutorial.
And I was wondering if there was a way to map a single line to multiple targets classes.

For example, I have the sentence "Jesus cures cancer" and want it to map to both 'sci.med' and 'soc.religion.christian'.

Is there a way to do that in SciKit?
Can I just put the same sentence twice with the different targets, or will that distort the final model?

Answer 1

What you are wanting to do is called multilabel classification; some scikit-learn classifiers support it, here's the documentation with more details.

If you put the same sentence twice into a model that is trying to predict one outcome, it will just confuse the model as one training example said it was one class and another said it was a different class and it is only learning to predict one class.