Learning Dual-Layer User Representation for Enhanced Item Recommendation

User representation learning is crucial for capturing different user preferences,but it is also critical challenging because user intentions are latent and dispersed in complex and different patterns of user-generated data,and thus cannot be measured directly.Text-based data models can learn user representations by mining latent semantics,which is beneficial to enhancing the semantic function of user representations.However,these technologies only extract common features in historical records and cannot represent changes in user intentions.However,sequential feature can express the user’s interests and intentions that change time by time.But the sequential recommendation results based on the user representation of the item lack the interpretability of preference factors.To address these issues,we propose in this paper a novel model with Dual-Layer User Representation,named DLUR,where the user’s intention is learned based on two different layer representations.Specifically,the latent semantic layer adds an interactive layer based on Transformer to extract keywords and key sentences in the text and serve as a basis for interpretation.The sequence layer uses the Transformer model to encode the user’s preference intention to clarify changes in the user’s intention.Therefore,this dual-layer user mode is more comprehensive than a single text mode or sequence mode and can effectually improve the performance of recommendations.Our extensive experiments on five benchmark datasets demonstrate DLUR’s performance over state-of-the-art recommendation models.In addition,DLUR’s ability to explain recommendation results is also demonstrated through some specific cases.

A Core Leader Based Label Propagation Algorithm for Community Detection

A large number of community discovery algorithms have been proposed in the last decade. Recently, the sharp increase of network scale has become a great challenge for traditional community discovery algorithms. Label propagation algorithm is a semi-supervised machine learning method, which has linear time complexity when coping with large scale networks. However, the output result has less stability and the quality of the output communities still remains to be improved. Therefore, we propose a novel coreleader based label propagation algorithm for community detection called CLBLPA. Firstly, we find core leaders of potential community by using a greedy method. Then we utilize the label influence potential to guide the process of label propagation. Thus we can accelerate the convergence of algorithm and improve the stability of the output. Experimental results on synthetic datasets and real networks show that CLBLPA can significantly improve the quality of the output communities.

Personalized Query Recommendation Using Semantic Factor Model

In the field of query recommendation,the current techniques for semantic analysis technology can’t meet the demands of users.In order to meet diverse needs,we improved the LDA model and designed a new query recommendation model based on collaborative filtering-Semantic Factor Model(SFM),which combines text information,user interest information and web source.First,we improved the LDA model from bag-of-word to bag-of-phrase to understand the topics expressed by users’frequently used sentences.The phrase bag model treats phrases as a whole and can capture more accurate query intent.Second,we use collaborative filtering to build an evaluation matrix between user interests and personalized expressions.Third,we designed a new scoring function that can recommend the top n resources to users.Finally,we conduct experiments on the AOL data set.The experimental results show that compared with other latest query recommendation techniques,SFM has higher recommendation quality.