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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

Document representation


The first step in the text classification process is to figure out how to represent the document in a manner which is suitable for classification tasks and learning algorithms. This step is basically intended to reduce the complexity of documents, making it easier to work with. While doing so, the following questions come to mind:

  • Do we need to preserve the order of words?

  • Is losing the information about the order a concern for us?

An attribute value representation of documents implies that the order of words in a document is not of high significance and each unique word in a document can be considered as a feature and the frequency of its occurrence is represented as a value. Further, discarding the features with a very low value or occurrence in the document can reduce the high dimensionality.

Vector space representation of words considers each word in a document as a vector. The attribute value representation may be having a Boolean form, set-of-words approach that...

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