Book Recommendation
System
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Under the Guidance of
Prof. Praveen M D
Contents
• Introduction
• Problem Statement
• Existing System
• System Design
• Methodology
• System Evaluation
• Course relevance
• References
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Introduction
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Are they effective??
(Celma & Lamere, ISMIR 2007)
 Netflix
2/3 rated movies are from recommendation
 Google News
38% more click-through are due tommendation
 Amazon
35% sales are from recommendation
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Introduction (Contd..)
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A recommendation system...
how its work?
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Introduction (Contd..)
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Recommender system (RS) help users
find items (e.g., news items,
movies,Books) that meet their
specific needs.
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Introduction (Contd..)
To recommend top-N most relevant books for a user, using
item based collaborative filtering & user based collaborative
filtering techniques and evaluating the performance of
these two techniques.
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Problem Statement
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3 Common Approaches
1.collaborative filtering
2.content-based filtering
3.hybrid recommender system
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Recommendation System
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Based on a description of the item and a profile of
the user’s preference (Brusilovsky Peter , 2007)
Content Based Filtering
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A method of making automatic predictions (filtering) about
the interests of a user by collecting preferences or taste
information from many users (collaborating)
Collaborative Filtering
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• Need to know about item content
– requires manual or automatic indexing
– Item features do not capture everything
• “User cold-start” problem
– Needs to learn what content features are important
for the user, so takes time
• What if user’s interests change?
Problems with Content Based Filtering:
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• Lack of serendipity
[Wikipedia: “the effect by which one accidentally
discovers something fortunate, especially while
looking for something entirely unrelated” ]
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Problems with Content Based Filtering:
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System Design
• User-based collaborative filtering
• Item-based collaborative filtering
Types Of Collaborative Filtering
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User & Item
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Order Data
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Order Data (Cont.)
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Order Data (Cont.)
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Similarity Calculation
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Similarity Calculation
Pearson’s Correlation
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Similarity Calculation Example
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K-Nearest Neighbor
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K-Nearest Neighbor
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Neighbor’s Ratings
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Remove Rated Items
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Calculating Final Score
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Item Similarity Calculation
Adjusted Cosine Similarity
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Item Similarity Calculation Example
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Item Similarity Calculation
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Similar Item
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• MAE—Mean Absolute Error
• RMSE--Root mean squared error
System Evaluation
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Course Relevance
THANK YOU
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Recommendation system