doiSerbia

A dual hybrid recommender system based on SCoR and the random forest

Panagiotakis Costas (Department of Management Science and Technology Hellenic Mediterranean University Agios Nikolaos, Crete, Greece), cpanag@hmu.gr
Papadakis Harris (Department of Electrical and Computer Engineering Hellenic Mediterranean University Heraklion, Crete, Greece), adanar@hmu.gr
Fragopoulou Paraskevi (Department of Electrical and Computer Engineering Hellenic Mediterranean University Heraklion, Crete, Greece), fragopou@ics.forth.gr

We propose a Dual Hybrid Recommender System based on SCoR, the Synthetic Coordinate Recommendation system, and the Random Forest method. By combining user ratings and user/item features, SCoR is initially employed to provide a recommendation which is fed into the Random Forest. The two systems are initially combined by splitting the training set into two “equivalent” parts, one of which is used to train SCoR while the other is used to train the Random Forest. This initial approach does not exhibit good performance due to reduced training. The resulted drawback is alleviated by the proposed dual training system which, using an innovative splitting method, exploits the entire training set for SCoR and the Random Forest, resulting to two recommender systems that are subsequently efficiently combined. Experimental results demonstrate the high performance of the proposed system on the Movielens datasets.

Keywords: recommender systems, synthetic coordinates, random forest