Calss 2: Spark ALS

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What you should do before the class

• Please read the below materials Spark AL sample code

Spark CFMF documentation

Matrix factorization techniques for recommender systems

Algorithmic Acceleration of Parallel ALS for Collaborative Filtering: Speeding up Distributed Big Data Recommendation in Spark

Large-Scale Parallel Collaborative Filtering for the Netflix Prize

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Please present the answer to the below questions

• What is ALS? Is it different from the common CFMF? (10 minutes)
• What's the difference between implicit and explicit data? How is Spark ALS treating then differently? (10 minutes)
• What is cold start problem in recommendation engine? How can you deal with it? (10 minutes)
• what are the major functions of the spark ALS API? (10 minutes)

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Spark installation

Install on mac Install on windows Install on linux