We have suggested how we might adjust our prior expectation for any one element of a collection using observations on a collection . When we evaluate a collection of adjusted expectations { , ..., }, we also implicitly evaluate the adjusted value for each element of , the collection of linear combinations of the elements of B, as, by the linearity of adjusted expectation (equation 2),
We now analyse changes in beliefs over . We consider B, D as vectors, of dimension r and k, respectively. We define the adjusted version of the collection B given D, , to be the `residual' vector
The properties of the adjusted vector are as for a single quantity, namely
the r dimensional null vector,
the null matrix.
Therefore, just as for a single quantity X, we partition the vector B as the sum of two uncorrelated vectors, namely
so that we may partition the variance matrix of B into two variance components
We call
the resolved variance matrix, for B by D. We call
the adjusted variance matrix, for B by D.
, are calculated as in equations 1, 8, namely