8 research outputs found
SetRank: A Setwise Bayesian Approach for Collaborative Ranking from Implicit Feedback
The recent development of online recommender systems has a focus on
collaborative ranking from implicit feedback, such as user clicks and
purchases. Different from explicit ratings, which reflect graded user
preferences, the implicit feedback only generates positive and unobserved
labels. While considerable efforts have been made in this direction, the
well-known pairwise and listwise approaches have still been limited by various
challenges. Specifically, for the pairwise approaches, the assumption of
independent pairwise preference is not always held in practice. Also, the
listwise approaches cannot efficiently accommodate "ties" due to the
precondition of the entire list permutation. To this end, in this paper, we
propose a novel setwise Bayesian approach for collaborative ranking, namely
SetRank, to inherently accommodate the characteristics of implicit feedback in
recommender system. Specifically, SetRank aims at maximizing the posterior
probability of novel setwise preference comparisons and can be implemented with
matrix factorization and neural networks. Meanwhile, we also present the
theoretical analysis of SetRank to show that the bound of excess risk can be
proportional to , where and are the numbers of items and
users, respectively. Finally, extensive experiments on four real-world datasets
clearly validate the superiority of SetRank compared with various
state-of-the-art baselines.Comment: This paper has been accepted in AAAI'2
Joint Representation Learning for Multi-Modal Transportation Recommendation
Multi-modal transportation recommendation has a goal of recommending a travel plan which considers various transportation modes, such as walking, cycling, automobile, and public transit, and how to connect among these modes. The successful development of multi-modal transportation recommendation systems can help to satisfy the diversified needs of travelers and improve the efficiency of transport networks. However, existing transport recommender systems mainly focus on unimodal transport planning. To this end, in this paper, we propose a joint representation learning framework for multi-modal transportation recommendation based on a carefully-constructed multi-modal transportation graph. Specifically, we first extract a multi-modal transportation graph from large-scale map query data to describe the concurrency of users, Origin-Destination (OD) pairs, and transport modes. Then, we provide effective solutions for the optimization problem and develop an anchor embedding for transport modes to initialize the embeddings of transport modes. Moreover, we infer user relevance and OD pair relevance, and incorporate them to regularize the representation learning. Finally, we exploit the learned representations for online multimodal transportation recommendations. Indeed, our method has been deployed into one of the largest navigation Apps to serve hundreds of millions of users, and extensive experimental results with real-world map query data demonstrate the enhanced performance of the proposed method for multimodal transportation recommendations