Chapter 4 Naive Bayes and Sentiment Classification

DEF text categorization is the task of assigning a label to an entire text.

TASK sentiment analysis is the extraction of sentiment.

Use handwritten rules can be fragile. Most are done via supervised machine learning, where we have a data set of input observations, each associated with some correct output(a "supervision signal"). The goal is to learn how to map an observation to a correct output.

DEF a probabilistic classifier gives the probability of the observation being in a class, in other words, a distribution.

DEF

• A generative classifier models how a class could generate some input data.

  • EX naive Bayes

• A discriminative classifier learn what features from the input are most useful to discriminate between possible classes.

  • EX logistic regression