Awesome article. Using cosine similarity to calculate product similarity is something I have been wanting to try. Have you thought about using running TFIDF on

Awesome article. Using cosine similarity to calculate product similarity is something I have been wanting to try. Have you thought about using running TFIDF on customers' entire purchase history and running cosine similarity between each customer's purchase history vectors and product vectors? I think an interesting study can be done on comparing the recommendation results between CF, Cosine similarity on products, and cosine similarity between customer history and products.