To develop a knowledge-aware recommender system,a key issue is how to obtain rich and structured knowledge base(KB)information for recommender system(RS)items.Existing data sets or methods either use side information ...To develop a knowledge-aware recommender system,a key issue is how to obtain rich and structured knowledge base(KB)information for recommender system(RS)items.Existing data sets or methods either use side information from original RSs(containing very few kinds of useful information)or utilize a private KB.In this paper,we present KB4Rec v1.0,a data set linking KB information for RSs.It has linked three widely used RS data sets with two popular KBs,namely Freebase and YAGO.Based on our linked data set,we first preform qualitative analysis experiments,and then we discuss the effect of two important factors(i.e.,popularity and recency)on whether a RS item can be linked to a KB entity.Finally,we compare several knowledge-aware recommendation algorithms on our linked data set.展开更多
Proactive dialogue generates dialogue utterance based on a conversation goal and a given knowledge graph(KG). Existing methods combine knowledge of each turn of dialogue with knowledge triples by hidden variables, res...Proactive dialogue generates dialogue utterance based on a conversation goal and a given knowledge graph(KG). Existing methods combine knowledge of each turn of dialogue with knowledge triples by hidden variables, resulting in the interpretability of generation results is relatively poor. An interpretable knowledge-aware path(KAP) model was proposed for knowledge reasoning in proactive dialogue generation.KAP model can transform explicit and implicit knowledge of each turn of dialogue into corresponding dialogue state matrix, thus forming the KAP for dialogue history. Based on KAP, the next turn of dialogue state vector can be infered from both the topology and semantic of KG. This vector can indicate knowledge distribution of next sentence, so it enhances the accuracy and interpretability of dialogue generation. Experiments show that KAP model’s dialogue generation is closer to actual conversation than other state-of-the-art proactive dialogue models.展开更多
为了解决就医过程中医疗资源短缺和患者时间不充裕、行程不便的问题,提出了结合外部知识的基于记忆网络的知识感知医疗对话生成模型(memory networks based knowledge-aware medical dialogue generation model,MKMed).该模型首先通过...为了解决就医过程中医疗资源短缺和患者时间不充裕、行程不便的问题,提出了结合外部知识的基于记忆网络的知识感知医疗对话生成模型(memory networks based knowledge-aware medical dialogue generation model,MKMed).该模型首先通过利用精确字匹配的方法在对话历史中进行实体追踪;随后在外部实体知识数据库里设计2阶段的实体预测,筛选出可能出现在回复中的医疗实体及对应知识,其中2阶段实体预测分别利用计算共现矩阵和余弦相似度的方法;模型接着用记忆网络来存储知识和对话历史的信息;最后整合记忆网络存储的信息,并使用注意力机制以及循环神经网络生成回复.在带有外部知识的大规模医疗对话数据集KaMed上进行了相关实验,该数据集为收集自在线平台的真实数据.实验结果表明提出的模型生成的回复在流畅性、多样性、正确性和专业性等方面均显著优于大部分基准模型.证明了合理引入外部知识的医疗对话模型能产生成更有医疗价值的回复.展开更多
知识感知推荐(KGR)领域普遍存在监督信号稀疏问题。为了解决这个问题,对比学习方法被越来越广泛地应用于KGR。但是,过去基于对比学习的KGR模型仍存在一些问题:首先,使用图卷积对所有邻居节点直接聚合,无法排除知识图谱中不必要邻居节点...知识感知推荐(KGR)领域普遍存在监督信号稀疏问题。为了解决这个问题,对比学习方法被越来越广泛地应用于KGR。但是,过去基于对比学习的KGR模型仍存在一些问题:首先,使用图卷积对所有邻居节点直接聚合,无法排除知识图谱中不必要邻居节点信息的干扰;此外,只关注全局视图的信息,忽略了局部特征,这会导致过平滑问题。为了解决以上问题,提出一种基于跨视图对比学习的知识感知推荐系统(knowledge-aware recommender system with cross-views contrastive learning,KRSCCL)。KRSCCL使用关系图注意力网络构建包含用户、物品和实体节点的全局视图;使用轻量级图卷积网络构建包含用户和物品节点的局部视图,强调局部特征,有效地缓解过平滑问题;最后,在构建的两个视图的图内和图间节点对之间进行对比学习,以充分提取知识图谱信号,优化用户和物品表示。为了验证模型的有效性,在3个不同领域的公开数据集上进行了实验,实验结果表明:关系图注意力网络可以有效排除复杂网络聚合时的噪声问题;引入局部视图可以优化节点表示生成,缓解过平滑问题;KRSCCL模型在这3个数据集上都表现良好,在电影领域数据集Movielens–1M上,推荐的评估指标F1分数较最强基线提升2.0%;在音乐领域数据集Last.FM上,F1分数较最强基线提升0.3%;在书籍领域数据集Book–Crossing上,F1分数较最强基线提升5.1%。证明了本文模型的有效性。展开更多
基金The work was partially supported by National Natural Science Foundation of China under the grant numbers 61872369,61832017 and 61502502.
文摘To develop a knowledge-aware recommender system,a key issue is how to obtain rich and structured knowledge base(KB)information for recommender system(RS)items.Existing data sets or methods either use side information from original RSs(containing very few kinds of useful information)or utilize a private KB.In this paper,we present KB4Rec v1.0,a data set linking KB information for RSs.It has linked three widely used RS data sets with two popular KBs,namely Freebase and YAGO.Based on our linked data set,we first preform qualitative analysis experiments,and then we discuss the effect of two important factors(i.e.,popularity and recency)on whether a RS item can be linked to a KB entity.Finally,we compare several knowledge-aware recommendation algorithms on our linked data set.
基金supported by the National Natural Science Foundation of China (61702047)。
文摘Proactive dialogue generates dialogue utterance based on a conversation goal and a given knowledge graph(KG). Existing methods combine knowledge of each turn of dialogue with knowledge triples by hidden variables, resulting in the interpretability of generation results is relatively poor. An interpretable knowledge-aware path(KAP) model was proposed for knowledge reasoning in proactive dialogue generation.KAP model can transform explicit and implicit knowledge of each turn of dialogue into corresponding dialogue state matrix, thus forming the KAP for dialogue history. Based on KAP, the next turn of dialogue state vector can be infered from both the topology and semantic of KG. This vector can indicate knowledge distribution of next sentence, so it enhances the accuracy and interpretability of dialogue generation. Experiments show that KAP model’s dialogue generation is closer to actual conversation than other state-of-the-art proactive dialogue models.
文摘为了解决就医过程中医疗资源短缺和患者时间不充裕、行程不便的问题,提出了结合外部知识的基于记忆网络的知识感知医疗对话生成模型(memory networks based knowledge-aware medical dialogue generation model,MKMed).该模型首先通过利用精确字匹配的方法在对话历史中进行实体追踪;随后在外部实体知识数据库里设计2阶段的实体预测,筛选出可能出现在回复中的医疗实体及对应知识,其中2阶段实体预测分别利用计算共现矩阵和余弦相似度的方法;模型接着用记忆网络来存储知识和对话历史的信息;最后整合记忆网络存储的信息,并使用注意力机制以及循环神经网络生成回复.在带有外部知识的大规模医疗对话数据集KaMed上进行了相关实验,该数据集为收集自在线平台的真实数据.实验结果表明提出的模型生成的回复在流畅性、多样性、正确性和专业性等方面均显著优于大部分基准模型.证明了合理引入外部知识的医疗对话模型能产生成更有医疗价值的回复.
文摘知识感知推荐(KGR)领域普遍存在监督信号稀疏问题。为了解决这个问题,对比学习方法被越来越广泛地应用于KGR。但是,过去基于对比学习的KGR模型仍存在一些问题:首先,使用图卷积对所有邻居节点直接聚合,无法排除知识图谱中不必要邻居节点信息的干扰;此外,只关注全局视图的信息,忽略了局部特征,这会导致过平滑问题。为了解决以上问题,提出一种基于跨视图对比学习的知识感知推荐系统(knowledge-aware recommender system with cross-views contrastive learning,KRSCCL)。KRSCCL使用关系图注意力网络构建包含用户、物品和实体节点的全局视图;使用轻量级图卷积网络构建包含用户和物品节点的局部视图,强调局部特征,有效地缓解过平滑问题;最后,在构建的两个视图的图内和图间节点对之间进行对比学习,以充分提取知识图谱信号,优化用户和物品表示。为了验证模型的有效性,在3个不同领域的公开数据集上进行了实验,实验结果表明:关系图注意力网络可以有效排除复杂网络聚合时的噪声问题;引入局部视图可以优化节点表示生成,缓解过平滑问题;KRSCCL模型在这3个数据集上都表现良好,在电影领域数据集Movielens–1M上,推荐的评估指标F1分数较最强基线提升2.0%;在音乐领域数据集Last.FM上,F1分数较最强基线提升0.3%;在书籍领域数据集Book–Crossing上,F1分数较最强基线提升5.1%。证明了本文模型的有效性。
