Text Mining With R.

Silge, Julia

Text Mining With R. - Primera edición - EE.UU Oreilly Media 2017 - 178 Páginas; Gráficos, tablas;

Much of the data available today is unstructured and text-heavy, making it challenging for analysts to apply their usual data wrangling and visualization tools. With this practical book, you’ll explore text-mining techniques with tidytext, a package that authors Julia Silge and David Robinson developed using the tidy principles behind R packages like ggraph and dplyr. You’ll learn how tidytext and other tidy tools in R can make text analysis easier and more effective.

The authors demonstrate how treating text as data frames enables you to manipulate, summarize, and visualize characteristics of text. You’ll also learn how to integrate natural language processing (NLP) into effective workflows. Practical code examples and data explorations will help you generate real insights from literature, news, and social media.

Preface
-Outline
-Topics This Book Does Not Cover
-About This Book
-Conventions Used in This Book
-Using Code Examples
-O’Reilly Safari
-How to Contact Us
-Acknowledgements
-1. The Tidy Text Format
-Contrasting Tidy Text with Other Data Structures
-The unnest_tokens Function
-Tidying the Works of Jane Austen
-The gutenbergr Package
-Word Frequencies
-Summary
-2. Sentiment Analysis with Tidy Data
-The sentiments Dataset
-Sentiment Analysis with Inner Join
-Comparing the Three Sentiment Dictionaries
-Most Common Positive and Negative Words
-Wordclouds
-Looking at Units Beyond Just Words
-Summary
-3. Analyzing Word and Document Frequency: tf-idf
-Term Frequency in Jane Austen’s Novels
-Zipf’s Law
-The bind_tf_idf Function
-A Corpus of Physics Texts
-Summary
-4. Relationships Between Words: N-grams and Correlations
-Tokenizing by N-gram
-Counting and Filtering N-grams
-Analyzing Bigrams
-Using Bigrams to Provide Context in Sentiment Analysis
-Visualizing a Network of Bigrams with ggraph
-Visualizing Bigrams in Other Texts
-Counting and Correlating Pairs of Words with the widyr Package
-Counting and Correlating Among Sections
-Examining Pairwise Correlation
-Summary
-5. Converting to and from Nontidy Formats
-Tidying a Document-Term Matrix
-Tidying DocumentTermMatrix Objects
-Tidying dfm Objects
-Casting Tidy Text Data into a Matrix
-Tidying Corpus Objects with Metadata
-Example: Mining Financial Articles
-Summary
-6. Topic Modeling
-Latent Dirichlet Allocation
-Word-Topic Probabilities
-Document-Topic Probabilities
-Example: The Great Library Heist
-LDA on Chapters
-Per-Document Classification
-By-Word Assignments: augment
-Alternative LDA Implementations
-Summary
-7. Case Study: Comparing Twitter Archives
-Getting the Data and Distribution of Tweets
-Word Frequencies
-Comparing Word Usage
-Changes in Word Use
-Favorites and Retweets
-Summary
-8. Case Study: Mining NASA Metadata
-How Data Is Organized at NASA
-Wrangling and Tidying the Data
-Some Initial Simple Exploration
-Word Co-ocurrences and Correlations
-Networks of Description and Title Words
-Networks of Keywords
-Calculating tf-idf for the Description Fields
-What Is tf-idf for the Description Field Words?
-Connecting Description Fields to Keywords
-Topic Modeling
-Casting to a Document-Term Matrix
-Ready for Topic Modeling
-Interpreting the Topic Model
-Connecting Topic Modeling with Keywords
-Summary
-9. Case Study: Analyzing Usenet Text
-Preprocessing
-Preprocessing Text
-Words in Newsgroups
-Finding tf-idf Within Newsgroups
-Topic Modeling
-Sentiment Analysis
-Sentiment Analysis by Word
-Sentiment Analysis by Message
-N-gram Analysis
-Summary
-Bibliography

9781491981658


Minería de textos
Análisis del sentimiento con datos ordenados.
Modelado de temas
Análisis N-gramo

004.3 / SI582