Book Image

Apache Spark 2: Data Processing and Real-Time Analytics

By : Romeo Kienzler, Md. Rezaul Karim, Sridhar Alla, Siamak Amirghodsi, Meenakshi Rajendran, Broderick Hall, Shuen Mei
Book Image

Apache Spark 2: Data Processing and Real-Time Analytics

By: Romeo Kienzler, Md. Rezaul Karim, Sridhar Alla, Siamak Amirghodsi, Meenakshi Rajendran, Broderick Hall, Shuen Mei

Overview of this book

Apache Spark is an in-memory, cluster-based data processing system that provides a wide range of functionalities such as big data processing, analytics, machine learning, and more. With this Learning Path, you can take your knowledge of Apache Spark to the next level by learning how to expand Spark's functionality and building your own data flow and machine learning programs on this platform. You will work with the different modules in Apache Spark, such as interactive querying with Spark SQL, using DataFrames and datasets, implementing streaming analytics with Spark Streaming, and applying machine learning and deep learning techniques on Spark using MLlib and various external tools. By the end of this elaborately designed Learning Path, you will have all the knowledge you need to master Apache Spark, and build your own big data processing and analytics pipeline quickly and without any hassle. This Learning Path includes content from the following Packt products: • Mastering Apache Spark 2.x by Romeo Kienzler • Scala and Spark for Big Data Analytics by Md. Rezaul Karim, Sridhar Alla • Apache Spark 2.x Machine Learning Cookbook by Siamak Amirghodsi, Meenakshi Rajendran, Broderick Hall, Shuen MeiCookbook
Table of Contents (23 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
Index

Topic modeling with Latent Dirichlet allocation in Spark 2.0


In this recipe, we will be demonstrating topic model generation by utilizing Latent Dirichlet Allocation to infer topics from a collection of documents.

We have covered LDA in previous chapters as it applies to clustering and topic modelling, but in this chapter, we demonstrate a more elaborate example to show its application to text analytics using more real-life and complex datasets.

We also apply NLP techniques such as stemming and stop words to provide a more realistic approach to LDA problem-solving. What we are trying to do is to discover a set of latent factors (that is, different from the original) that can solve and describe the solution in a more efficient way in a reduced computational space.

The first question that always comes up when using LDA and topic modelling is what is Dirichlet? Dirichlet is simply a type of distribution and nothing more. Please see the following link from the University of Minnesota for details...