Dynamic interaction graphs have been widely adopted to model the evolution of
user-item interactions over time. There are two crucial factors when modelling
user preferences for link prediction in dynamic interaction graphs: 1)
collaborative relationship among users and 2) user personalized interaction
patterns. Existing methods often implicitly consider these two factors
together, which may lead to noisy user modelling when the two factors diverge.
In addition, they usually require time-consuming parameter learning with
back-propagation, which is prohibitive for real-time user preference modelling.
To this end, this paper proposes FreeGEM, a parameter-free dynamic graph
embedding method for link prediction. Firstly, to take advantage of the
collaborative relationships, we propose an incremental graph embedding engine
to obtain user/item embeddings, which is an Online-Monitor-Offline architecture
consisting of an Online module to approximately embed users/items over time, a
Monitor module to estimate the approximation error in real time and an Offline
module to calibrate the user/item embeddings when the online approximation
errors exceed a threshold. Meanwhile, we integrate attribute information into
the model, which enables FreeGEM to better model users belonging to some under
represented groups. Secondly, we design a personalized dynamic interaction
pattern modeller, which combines dynamic time decay with attention mechanism to
model user short-term interests. Experimental results on two link prediction
tasks show that FreeGEM can outperform the state-of-the-art methods in accuracy
while achieving over 36X improvement in efficiency. All code and datasets can
be found in this https URL.

本文提出了一种无需反向传播进行参数学习的动态图嵌入方法 FreeGEM，通过一个增量式图嵌入引擎、一个模型监控模块以及一个离线校准模块，充分考虑用户协同关系和用户个性化行为模式，同时融合属性信息来更好地模拟用户群体，因此在准确度和效率方面比现有方法表现更好。