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Mastering Text Mining with R

You're reading from   Mastering Text Mining with R Extract and recognize your text data

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Product type Paperback
Published in Dec 2016
Publisher Packt
ISBN-13 9781783551811
Length 258 pages
Edition 1st Edition
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Author (1):
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KUMAR ASHISH KUMAR ASHISH
Author Profile Icon KUMAR ASHISH
KUMAR ASHISH
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Toc

Dimensionality reduction

Complex and noisy characteristics of textual data with high dimensions can be handled by dimensionality reduction techniques. These techniques reduce the dimension of the textual data while still preserving its underlying statistics. Though the dimensions are reduced, it is important to preserve the inter-document relationships. The idea is to have minimum number of dimensions, which can preserve the intrinsic dimensionality of the data.

A textual collection is mostly represented in the form of a term document matrix wherein we have the importance of each term in a document. The dimensionality of such a collection increases with the number of unique terms. If we were to suggest the simplest possible dimensionality reduction method, that would be to specify the limit or boundary on the distribution of different terms in the collection. Any term that occurs with a significantly high frequency is not going to be informative for us, and the barely present terms can undoubtedly...

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