Sayan Chakraborty, Arnab Bhattacharjee, Taps Maiti, Structural Factorization of Latent Adjacency Matrix, with an application to Auto Industry Networks, Sankhyā: The Indian Journal of Statistics, ...

In Civ 6, Adjacency Bonuses confer extra yields to Districts from specific Terrain or other tile types, but it's a little more complex than just that.