The paper lacks a detailed discussion of the computational complexity and scalability of the proposed GMAN model, especially for large road networks. This makes it difficult to assess the practical applicability of the model in real-world scenarios.
Limited Dataset Diversity
The paper primarily evaluates GMAN on two datasets, Xiamen and PeMS. More extensive evaluation on diverse datasets with varying characteristics (e.g., size, topology, traffic patterns) is necessary to establish the generalizability and robustness of the proposed approach.
Static Road Network Assumption
The paper assumes that the road network structure is static. However, in reality, road networks can change over time due to constructions, accidents, or other events. The model's ability to adapt to dynamic road network changes is not addressed.
The paper focuses on predicting traffic volume and speed. The applicability of GMAN to other traffic-related tasks, such as predicting traffic flow or density, is not explored.