I couldn't find any direct information on "usage Vector" in the provided search results. However, I can tell you that the search results are related to predicting probabilities of usage of shopping-mall corridors using graph neural networks.

If you could provide more context or clarify what you mean by "usage Vector," I'd be happy to try and help you further. Alternatively, if you're looking for information on vectors in general, I can try and provide some general knowledge on the topic.