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Machine learning with R : expert techniques for predictive modeling to solve all your data analysis problems /

Perhaps you already know a bit about machine learning but have never used R, or perhaps you know a little R but are new to machine learning. In either case, this book will get you up and running quickly. It would be helpful to have a bit of familiarity with basic programming concepts, but no prior e...

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Detalles Bibliográficos
Clasificación:Libro Electrónico
Autor principal: Lantz, Brett (Autor)
Formato: Electrónico eBook
Idioma:Inglés
Publicado: Birmingham : Packt Publishing, [2015]
Edición:Second edition.
Colección:Community experience distilled.
Temas:
Acceso en línea:Texto completo (Requiere registro previo con correo institucional)
Tabla de Contenidos:
  • Cover; Copyright; Credits; About the Author; About the Reviewers; www.PacktPub.com; Table of Contents; Preface; Chapter 1: Introducing Machine Learning; The origins of machine learning; Uses and abuses of machine learning; Machine learning successes; The limits of machine learning; Machine learning ethics; How machines learn; Data storage; Abstraction; Generalization; Evaluation; Machine learning in practice; Types of input data; Types of machine learning algorithms; Matching input data to algorithms; Machine learning with R; Installing R packages; Loading and unloading R packages; Summary.
  • Chapter 2: Managing and Understanding DataR data structures; Vectors; Factors; Lists; Data frames; Matrixes and arrays; Managing data with R; Saving, loading, and removing R data structures; Importing and saving data from CSV files; Exploring and understanding data; Exploring the structure of data; Exploring numeric variables; Measuring the central tendency
  • mean and median; Measuring spread
  • quartiles and the five-number summary; Visualizing numeric variables
  • boxplots; Visualizing numeric variables
  • histograms; Understanding numeric data
  • uniform and normal distributions.
  • Measuring spread
  • variance and standard deviationExploring categorical variables; Measuring the central tendency
  • the mode; Exploring relationships between variables; Visualizing relationships
  • scatterplots; Examining relationships
  • two-way cross-tabulations; Summary; Chapter 3: Lazy Learning
  • Classification Using Nearest Neighbors; Understanding nearest neighbor classification; The k-NN algorithm; Measuring similarity with distance; Choosing an appropriate k; Preparing data for use with k-NN; Why is the k-NN algorithm lazy?; Example
  • Diagnosing breast cancer with the k-NN algorithm.
  • Step 1
  • collecting dataStep 2
  • exploring and preparing the data; Transformation
  • normalizing numeric data; Data preparation
  • creating training and test datasets; Step 3
  • training a model on the data; Step 4
  • evaluating model performance; Step 5
  • improving model performance; Transformation
  • z-score standardization; Testing alternative values of k; Summary; Chapter 4: Probabilistic Learning
  • Classification Using Naive Bayes; Understanding Naive Bayes; Basic concepts of Bayesian methods; Understanding probability; Understanding joint probability.
  • Computing conditional probability with Bayes' theoremThe Naive Bayes algorithm; Classification with Naive Bayes; The Laplace estimator; Using numeric features with Naive Bayes; Example
  • filtering mobile phone spam with the Naive Bayes algorithm; Step 1
  • collecting data; Step 2
  • exploring and preparing the data; Data preparation
  • cleaning and standardizing text data; Data preparation
  • splitting text documents into words; Data preparation
  • creating training and test datasets; Visualizing text data
  • word clouds; Data preparation
  • creating indicator features for frequent words.
  • Step 3
  • training a model on the data.