The similarity scores along with the list of nearest-neighbors are transferred to the target domain to form a set of weighted samples, D, which can be used to estimate the unknown parame- The main purpose of assigning a sample weight w l to each of the pseudo observations u l is that by doing so, users with a higher source-domain similarity to user i will have a larger impact on the estimation of the target-domain parameters (µ i , Σ i ).
with this model specication, the similarity between users is transferred across domains.