Steve Nassar of Alpine Mortgage (503) 805-5582 snassar@alpinemc.com has shared the following great info on all sorts of lending topics. Read on- 
I get asked about about credit scores all the time, particularly because there are 3 different sources from which they come. I recently spoke with Bruce Howard of Landover Mortgage (his link is below) and he stated that the credit score is derived by pulling all three scores (Equifax, TransUnion, Experian) and using the report score that falls in the middle. If two applicants are involved then the same method is used taking the lower score of the two applicants.