Getting the newsgroups data

The project in this chapter is about the 20 newsgroups dataset. It's composed of text taken from newsgroup articles, as its name implies. It was originally collected by Ken Lang and now has been widely used for experiments in text applications of machine learning techniques, specifically NLP techniques.

The data contains approximately 20,000 documents across 20 online newsgroups. A newsgroup is a place on the internet where people can ask and answer questions about a certain topic. The data is already cleaned to a certain degree and already split into training and testing sets. The cutoff point is at a certain date.

The original data comes from http://qwone.com/~jason/20Newsgroups/, with 20 different topics listed, as follows:

• comp.graphics
• comp.os.ms-windows.misc
• comp.sys.ibm.pc.hardware
• comp.sys.mac.hardware
• comp.windows.x
• rec.autos
• rec.motorcycles
• rec.sport.baseball
• rec...