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practical-recommender-systems / moviegeek

A django website used in the book Practical Recommender Systems to illustrate how recommender algorithms can be implemented.
MIT License
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The value of similarity matrix may be wrong #62

Open yoheimiyamoto opened 2 years ago

yoheimiyamoto commented 2 years ago

Chapter8 Collaborative filtering in the neighborhood

8.4 Amazon's algorithm to precalculate item similarity

Sim("MIB", "ST") was 0.016 with the following calculation .

Screen Shot 2022-05-28 at 9 22 33

However, in the Similarity matrix explained later, a completely different value is set, Sim (MIB, ST) is 0.63.

Table 8.4

Screen Shot 2022-05-28 at 9 23 44

.

pprafaellima commented 10 months ago

I've noticed the same issue. Have you figured out?