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COMP 4332 Tutorial 10

April 12

Yin Zhu

yinz@cse.ust.hk

CF tools

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Models & Tools• KNN Models

• Implement yourself

• Matrix Factorization Models• Probabilistic MF [DEMO]• Factorization machines [DEMO]

KNN Model• Similar-User based Prediction:

• Similar-Item based Prediction:

Neighborhood similarity

Normalization factor

Base rating

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Matrix Factorization

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Predicting missing values as recommendation

Matrix Factorization Model

Xm

n

m

n

UVT k

k

User parameters

Item parameters

𝑥𝑢𝑖=𝛼𝑢+𝛽𝑖+𝑢𝑖❑𝑇𝑣𝑢

Base Ratings

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PMF Demo• Matlab code:

• http://www.mit.edu/~rsalakhu/BPMF.html

• Implement PMF & Bayesian PMF• PMF is much faster than BPMF

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Factorization Machine Demo• libFM, its manual and paper