Google News Personalization: Scalable Online Collaborative Filtering 

- Generate recommendations using 3 Approaches
        Collaborative Filtering using MinHash clustering
        Probabilistic Latent Semantic Indexing ( PLSI )
        Covisitation counts
- We combine recommendations from different algorithms using a linear model
- user clustering using Minhash and PLSI

Efficient Clustering of High-Dimensional Data Sets with Application to Reference Matching 

- Canopies can be applied to many domains and used with a variety of clustering approaches, including 

            Greedy Agglomerative Clustering,

            K-means and 

            Expectation-Maximization.

- we do not calculate the distance between two points that never appear in the same canopy, i.e. we assume their distance to be infinite.