Book Image

Spark for Data Science

By : Srinivas Duvvuri, Bikramaditya Singhal
Book Image

Spark for Data Science

By: Srinivas Duvvuri, Bikramaditya Singhal

Overview of this book

This is the era of Big Data. The words ‘Big Data’ implies big innovation and enables a competitive advantage for businesses. Apache Spark was designed to perform Big Data analytics at scale, and so Spark is equipped with the necessary algorithms and supports multiple programming languages. Whether you are a technologist, a data scientist, or a beginner to Big Data analytics, this book will provide you with all the skills necessary to perform statistical data analysis, data visualization, predictive modeling, and build scalable data products or solutions using Python, Scala, and R. With ample case studies and real-world examples, Spark for Data Science will help you ensure the successful execution of your data science projects.
Table of Contents (18 chapters)
Spark for Data Science
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface

Training an SVM


While training an SVM, the modeler has to take a number of decisions:

  • How to pre-process the data (transformation and scaling). The categorical variables should be converted to numeric ones by dummifying them. Also, scaling the numeric values is needed (either 0 to 1 or -1 to +1).

  • Which kernel to use (check using cross-€“validation if you are unable to visualize the data and/ or conclude on it).

  • What parameters to set for the SVM: penalty parameter and the kernel parameter (find using cross-€“validation or grid search)

If needed, you can use an entropy based feature selection to include only the important features in your model.

Scala:

scala> import org.apache.spark.mllib.classification.{SVMModel, SVMWithSGD}
import org.apache.spark.mllib.classification.{SVMModel, SVMWithSGD}
scala> import org.apache.spark.mllib.evaluation.BinaryClassificationMetrics
import org.apache.spark.mllib.evaluation.BinaryClassificationMetrics
scala> import org.apache.spark.mllib.util.MLUtils...