Book Image

Practical Data Science Cookbook, Second Edition - Second Edition

By : Prabhanjan Narayanachar Tattar, Bhushan Purushottam Joshi, Sean Patrick Murphy, ABHIJIT DASGUPTA, Anthony Ojeda
Book Image

Practical Data Science Cookbook, Second Edition - Second Edition

By: Prabhanjan Narayanachar Tattar, Bhushan Purushottam Joshi, Sean Patrick Murphy, ABHIJIT DASGUPTA, Anthony Ojeda

Overview of this book

As increasing amounts of data are generated each year, the need to analyze and create value out of it is more important than ever. Companies that know what to do with their data and how to do it well will have a competitive advantage over companies that don’t. Because of this, there will be an increasing demand for people that possess both the analytical and technical abilities to extract valuable insights from data and create valuable solutions that put those insights to use. Starting with the basics, this book covers how to set up your numerical programming environment, introduces you to the data science pipeline, and guides you through several data projects in a step-by-step format. By sequentially working through the steps in each chapter, you will quickly familiarize yourself with the process and learn how to apply it to a variety of situations with examples using the two most popular programming languages for data analysis—R and Python.
Table of Contents (17 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface

Finding the highest-scoring movies


If you're looking for a good movie, you'll often want to see the most popular or best-rated movies overall. Initially, we'll take a naïve approach to compute a movie's aggregate rating by averaging the user reviews for each movie. This technique will also demonstrate how to access the data in our MovieLens class.

Getting ready

These recipes are sequential in nature. Thus, you should have completed the previous recipes in this chapter before starting with this one.

How to do it...

Follow these steps to output numeric scores for all movies in the dataset and compute a top-10 list:

  1. Augment the MovieLens class with a new method to get all reviews for a particular movie:
In [8]: class MovieLens(object):
...:
...:
...: def reviews_for_movie(self, movieid):
...: """
...: Yields the reviews for a given movie
...: """
...: for review in self.reviews.values():
...: if movieid in review:
...: yield review[movieid]
...: 
  1. Then, add an additional method to compute the top...