Exercise

Preparing the dtm

You are given a dataframe df containing 90 abstracts of NSF awards. Its three columns are Abstract, AwardNumber, and field. Your task is to construct a document-term matrix, with stop words being filtered out. Use AwardNumber as the document ID.

Instructions

100 XP

Split the Abstract column into tokens.
Remove stopwords.
Count the number of occurrences.
Create a document term matrix.