PySpark and AWS: Master Big Data with PySpark and AWS - Finding Average-2

The video tutorial explains the process of calculating the average rating of movies from a dataset using transformations in RDD. It covers the steps to calculate total ratings and counts, and then find the average using a mapper function. The tutorial emphasizes understanding the logical flow and encourages practice through quizzes.

What is the primary goal of the transformations discussed in the first section?

• To calculate the sum of all data points

• To filter out unwanted data

• To sort the dataset in ascending order

• To find the average of a dataset

What does the 'reduce by key' function help achieve in the context of RDDs?

• It sorts the data alphabetically

• It filters out duplicate entries

• It combines values with the same key

• It splits the data into multiple partitions

In the example provided, how many times is 'The Godfather' movie rated in the dataset?

• Five times

• Four times

• Three times

• Two times

What is the purpose of using a Lambda function in the mapper?

• To convert strings to integers

• To filter out null values

• To calculate the average rating

• To sort the data

What is the first element of the tuple in the mapper function?

• The movie's total rating

• The number of ratings

• The average rating

• The movie name

What is the final output of the complete logical flow discussed in the last section?

• The total number of movies

• The average rating of each movie

• The list of all movie names

• The highest rated movie

Why is it recommended to practice the steps before attempting the quizzes?

• To memorize the code

• To complete the course faster

• To avoid making any mistakes

• To develop a deeper understanding