Creating new classifications Is it possible for an algorithm to predict a new class that has never been before in training? For example, in my training data I have: 

I need a flight to Boston --&gt; flight query

What is two plus two --&gt; math query

Who is the president of the United States --&gt; Donald Trump

How can I make a model that can predict a new class for:

How are you today --&gt; ??? (Should be something like conversation query)


I am almost looking for a way to combine supervised learning and unsupervised learning. Using supervised learning for a model to predict new classes (unsupervised learning)
Do you mean a class label that the algorithm has never seen before? Then no, it is not possible. If you dont have labelled data for all your samples you can run a LDA, to get some topics and then assign labels based on the topics obtained. Even this approach wouldnt be really great. Since your problem is classification, I would recommend restricting your domain and using only samples for which the label is known. For better classification accuracy you can look into CNN.