  The overwhelming volume and complexity of information in online applications
make recommendation essential for users to find information of interest.
However, two major limitations that coexist in real world applications (1)
incomplete user profiles, and (2) the dynamic nature of user preferences
continue to degrade recommender quality in aspects such as timeliness,
accuracy, diversity and novelty. To address both the above limitations in a
single solution, we propose a novel cross-network time aware recommender
solution. The solution first learns historical user models in the target
network by aggregating user preferences from multiple source networks. Second,
user level time aware latent factors are learnt to develop current user models
from the historical models and conduct timely recommendations. We illustrate
our solution by using auxiliary information from the Twitter source network to
improve recommendations for the YouTube target network. Experiments conducted
using multiple time aware and cross-network baselines under different time
granularities show that the proposed solution achieves superior performance in
terms of accuracy, novelty and diversity.
