Getting Started with Natural Language Processing

9 Topic analysis

This chapter covers

• Implementing a supervised approach to topic classification with scikit-learn
• Using multiclass classification for NLP tasks
• Discovering topics in an unsupervised way
• Implementing an unsupervised approach—clustering with scikit-learn

In this chapter, you will learn how to automatically detect topics in text, either selecting from the set of known topics or discovering new, previously unseen ones. This is a challenging and practically useful task that can be approached from different perspectives using a variety of methods. This chapter will introduce new techniques, some of which are closely related to the ones that you’ve been using before. Let’s put this task in a broader context before diving deep into ...