ABSTRACT
As a kind of introduction, the Classification chapter mentions the procedure used to describe and demonstrate subsequent chapters on classification using various selected algorithms, justifying briefly their choice for the specific focusing this publication on its goal, and their implementations through freely accessible R packages (everything may be downloaded from the Internet). Several original examples of text documents (Internet reviews of books by their readers and shoppers) from the real world are shown. The reviews represent two classes: positive (five stars by reviewers) and negative (one star. Then, a list of selected algorithms follows, including how the classification efficiency was evaluated.
