Book Image

Advanced Machine Learning with R

By : Cory Lesmeister, Dr. Sunil Kumar Chinnamgari
Book Image

Advanced Machine Learning with R

By: Cory Lesmeister, Dr. Sunil Kumar Chinnamgari

Overview of this book

R is one of the most popular languages when it comes to exploring the mathematical side of machine learning and easily performing computational statistics. This Learning Path shows you how to leverage the R ecosystem to build efficient machine learning applications that carry out intelligent tasks within your organization. You’ll work through realistic projects such as building powerful machine learning models with ensembles to predict employee attrition. Next, you’ll explore different clustering techniques to segment customers using wholesale data and even apply TensorFlow and Keras-R for performing advanced computations. Each chapter will help you implement advanced machine learning algorithms using real-world examples. You’ll also be introduced to reinforcement learning along with its use cases and models. Finally, this Learning Path will provide you with a glimpse into how some of these black box models can be diagnosed and understood. By the end of this Learning Path, you’ll be equipped with the skills you need to deploy machine learning techniques in your own projects.
Table of Contents (30 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Word frequency


With word frequency analysis, we want to clean this data by removing the stop words, which would just clutter our interpretation. We'll explore the top overall word frequencies, then take a look at President Lincoln's work.

Word frequency in all addresses

To get rid of stop words in a tidy format, you can use the stop_words data frame provided in the tidytext package. You call that tibble into the environment, then do an anti-join by word:

> library(tidytext)

> data(stop_words)

> sotu_tidy <- sotu_unnest %>%
    dplyr::anti_join(stop_words, by = "word")

Notice that the length of the data went from 1.97 million observations down to 778,161. Now, you can go ahead and see the top words. I don't do it in the following, but you can put this into a data frame if you so choose: 

> sotu_tidy %>%
    dplyr::count(word, sort = TRUE)
# A tibble: 29,558 x 2
   word           n
   <chr>      <int>
 1 government  7573
 2 congress    5759
 3 united      5102...