Collaborative filtering

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Main Article

Discussion

Definition

A Collaborative Filtering(CF) refers to the use of software algorithms for narrowing down a large set of choices by using collaboration among multiple agents, viewpoints, and data sources.

Overview

The term Collaborative Filtering was first by the makers of one of the first recommendation systems, Tapestry. The basic assumption in CF is that user A and user B's personal tastes are co-related if both users rate n items similarly.

Collaborative Filtering systems follow this approach to produce recommendations:
1. Gather ratings from users or maintain user's ratings in a database.
2. Computing the correlations between pairs of users to identify a user’s neighbors in taste space
3. Combine the ratings of these neighbors to make recommendations.