Title
Exact-K Recommendation via Maximal Clique Optimization.
Abstract
This paper targets to a novel but practical recommendation problem named exact-K recommendation. It is different from traditional top-K recommendation, as it focuses more on (constrained) combinatorial optimization which will optimize to recommend a whole set of K items called card, rather than ranking optimization which assumes that "better" items should be put into top positions. Thus we take the first step to give a formal problem definition, and innovatively reduce it to Maximum Clique Optimization based on graph. To tackle this specific combinatorial optimization problem which is NP-hard, we propose Graph Attention Networks (GAttN) with a Multi-head Self-attention encoder and a decoder with attention mechanism. It can end-to-end learn the joint distribution of the K items and generate an optimal card rather than rank individual items by prediction scores. Then we propose Reinforcement Learning from Demonstrations (RLfD) which combines the advantages in behavior cloning and reinforcement learning, making it sufficient-and-efficient to train the model. Extensive experiments on three datasets demonstrate the effectiveness of our proposed GAttN with RLfD method, it outperforms several strong baselines with a relative improvement of 7.7% and 4.7% on average in Precision and Hit Ratio respectively, and achieves state-of-the-art (SOTA) performance for the exact-K recommendation problem.
Year
DOI
Venue
2019
10.1145/3292500.3330832
KDD
Keywords
Field
DocType
encoder-decoder, exact-k recommendation, learning-to-rank, recommender system, reinforcement learning
Recommender system,Learning to rank,Joint probability distribution,Ranking,Clique,Computer science,Combinatorial optimization,Artificial intelligence,Encoder,Machine learning,Reinforcement learning
Journal
Volume
ISBN
Citations 
abs/1905.07089
978-1-4503-6201-6
5
PageRank 
References 
Authors
0.45
0
8
Name
Order
Citations
PageRank
Yu Gong11328.35
Yu Zhu2976.67
Lu Duan3132.80
Qingwen Liu496562.14
Ziyu Guan555338.43
Fei Sun621815.99
Wenwu Ou719115.56
Kenny Qili Zhu840039.16