Multimodal recommender systems have emerged as a pivotal paradigm for harnessing diverse data modalities to deliver personalized services. Contemporary research predominantly focuses on integrating heterogeneous modality information through graph learning. However, these approaches face two key challenges: (1) the inherent complexity of modalities, characterized by entangled redundant signals and noise; and (2) the challenge of effectively integrating multimodal representations, each of which may exert varying degrees of influence on users' preferences. To address these challenges, we propose a novel Collaboration-Guided Multimodal Disentanglement and Hierarchical Fusion for Recommendation (DHMRec), which simultaneously achieves intra-modal denoising disentanglement and inter-modal hierarchical fusion. Specifically, we introduce a collaboration-related modality disentanglement module to distinguish between modality-common and modality-specific features. Then, through multi-view graph learning to capture both item-item dependencies and user-item interaction patterns. Additionally, we implement hierarchical fusion between the disentangled multimodal features and ID embeddings using a positive-negative attention-aware fusion module and an interaction distribution-based alignment module. Extensive experiments on three benchmarks demonstrate that our DHMRec surpasses various state-of-the-art baselines, highlighting its effectiveness in intra-modal disentanglement and multimodal features fusion.

With the rapid development of scientific research, a large amount of literature materials (e.g., published papers) has brought a serious information overload problem to researchers. For those novices who have just stepped into a certain research field, the fact that they do not yet know their own research direction, coupled with the huge amount of literature materials and their varying quality, makes it even more difficult for them to retrieve high-quality papers. To this end, we propose a Cross-community academic Knowledge Graph based approach for machine learning paper Recommendation (CKGR). Considering the hierarchical structure of cross-community knowledge graphs, we utilize knowledge propagation in hyperbolic space for entity representation learning. To alleviate the data sparsity problem as well as to learn better entity representations, we further introduce a preference migration module and contrastive learning. Meanwhile, considering the semantic relationships among entities, we introduce textual information to enhance the connection among interacting nodes for better recommendation tasks.

As auxiliary collaborative signals, the entity connectivity and relation semanticity beneath knowledge graph (KG) triples can alleviate the data sparsity and cold-start issues of recommendation tasks. Thus many works consider obtaining user and item representations via information aggregation on graph-structured data within Euclidean space. However, the scale-free graphs (e.g., KGs) inherently exhibit non-Euclidean geometric topologies, such as tree-like and circle-like structures. The existing recommendation models built in a single type of embedding space do not have enough capacity to embrace various geometric patterns, consequently, resulting in suboptimal performance. To address this limitation, we propose a KG-aware recommendation model with mixed-curvature manifolds interaction learning, namely CurvRec. On the one hand, it aims to preserve various global geometric structures in KG with mixed-curvature manifold spaces as the backbone. On the other hand, we integrate Ricci curvature into graph convolutional networks (GCNs) to capture local geometric structural properties when aggregating neighbor nodes. Besides, to exploit the expressive spatial features in KG, we incorporate interaction learning to ensure the geometric message passing between curved manifolds. Specifically, we adopt curvature-aware geodesic distance metrics to maximize the mutual information between Euclidean space and non-Euclidean spaces. Through extensive experiments, we demonstrate that the proposed CurvRec outperforms state-of-the-art baselines.

Knowledge graph (KG) has been widely used in the field of recommender systems. There are some nodes in KG that guide the occurrence of interaction behaviors. We call them guided nodes. However, the current application doesn’t take into account the guided nodes in KG. We explore the utility of guided nodes in KG. It is applied in repository recommendations. In this paper, we propose an end-to-end framework, namely Guided Node Graph Convolutional Network (GNGCN), which effectively captures the connections between entities by mining the influence of related nodes. We extract samples of each entity in KG as their guided nodes and then combine the information and bias of the guided nodes when computing the representation of a given entity. The guided nodes can be extended to multiple hops. We evaluate our model on a real-world Github dataset named Github-SKG and music recommendation dataset, and the experimental results show that the method outperforms the recommendation baselines and our model is much lighter than others.

The explosive growth of machine learning (ML) methods is overloading users with choices for learning tasks. Method recommendation aims to alleviate this problem by selecting the most appropriate ML methods for given learning tasks. Recent research shows that the descriptive and structural information of the knowledge graphs (KGs) can significantly enhance the performance of ML method recommendation. However, existing studies have not fully explored the descriptive information in KGs, nor have they effectively exploited the descriptive and structural information to provide the necessary supervision. To address these limitations, we distinguish descriptive attributes from the traditional relationships in KGs with the rest as structural connections to expand the scope of KG descriptive information. Based on this insight, we propose the Cross-modal Knowledge Graph Contrastive learning (CKGC) approach, which regards information from descriptive attributes and structural connections as two modalities, learning informative node representations by maximizing the agreement between the descriptive view and the structural view. Through extensive experiments, we demonstrate that CKGC significantly outperforms the state-of-the-art baselines, achieving around 2% higher accurate click-through-rate (CTR) prediction, over 30% more accurate top-10 recommendation, and over 50% more accurate top-20 recommendation compared to the best performing existing approach.

The huge number of machine learning (ML) methods has resulted in significant information overload. Faced with an overwhelming number of ML methods, it is challenging to select appropriate ones for the given dataset and task. In general, the names of ML methods or datasets are rather condensed, thus lacking specific explanations, while the rich latent relationships between ML entities are not fully explored. In this paper, we propose a description-enhanced machine learning knowledge graph-based approach - DEKR - to help recommend appropriate ML methods for given ML datasets. The proposed knowledge graph (KG) not only includes the connections between entities but also contains the descriptions of the dataset and method entities. DEKR fuses the structural information with the description information of entities in the knowledge graph. It is a deep hybrid recommendation framework, which incorporates the knowledge graph-based and text-based methods, overcoming the limitations of previous knowledge graph-based recommendation systems that ignore the description information. There are two key components of DEKR: 1) a graph neural network aggregating information from multi-order neighbors with attention to enrich the seed (i.e. dataset or method) node's own representation, and 2) a deep collaborative filtering network based on the description text to obtain the linear and nonlinear interactions of description features. Through extensive experiments, we demonstrated the efficiency of DEKR, which outperforms the current state-of-the-art baselines by a large margin.

At present, software development is an important way to make our life more convenient and intelligent. With the development of software programming, we have accumulated a lot of expert experience and common sense of domain knowledge. How to effectively organize and reuse these high-quality knowledge has become an urgent problem because reusing high-quality expert knowledge can greatly improve the efficiency of solving problems, especially for the novices of programming. When we encounter the programming problems, the usual solutions to get the answers is to query the search engines or consult the senior developers. However, these solutions have the following limitations: 1) the information in the field of software development is relatively scattered, for example, the demanded information is distributed on different websites. The developers need to query the search engine several times to get the information that they want, which is unfriendly, especially for the novices; 2) there is no such a unified organization form for the information we retrieve, and we need to process it further to get the answers, which is inefficient. To address the above limitations, we propose to build a software development knowledge graph (SoftKG) through Wikipedia taxonomy. Specifically, we propose a framework to build SoftKG based on open source knowledge communities.