If we adjust each member of the base by D, then we obtain a new base , the base of adjusted versions of the elements of B. We call this the base adjusted by , written {B/D}. The belief structure with this base is termed the adjusted belief structure of B by D and is written . To simplify our notation, we also use to represent the vector , where appropriate.
We may view as representing a belief structure over the linear space . However, it is also useful to view as an inner product space constructed over the linear space but with the covariance inner product replaced by the adjusted covariance inner product
We now analyse the differences between the variance and the adjusted variance inner products.