Partial variances

To show the effects of partial adjustment upon the variances of the quantities of interest, we use the pv  option to the SHOW:  command:

BD>show: pv

 
Figure 26:  Partial adjustment variation

giving the output shown in figure 26. (This is discussed further in section 6.2.1.) Reading from left to right, and using to illustrate, we see

• the name of the element, ;
• the adjustment variance for the element after the initial adjustment, ;
• the adjustment variance for the element taking into account the additional partial adjustment, that is ;
• the difference between the first two quantities, representing the variance resolved by the partial adjustment, ;
• the partial resolution, , being the proportion of variation resolved relative to the initial variance in ;
• the proportion of variance resolved by the partial adjustment, relative to the adjustment variance in prior to the partial adjustment. In terms of summarising the reduction in variance for (the adjusted version of given ), this is .

The final row of the output gives analagous results for uncertainties over the belief structure taken as a whole. Reading from left to right we see:

• the name of the structure, ;
• the adjustment uncertainty for the structure after the initial adjustment, ;
• the adjustment uncertainty for the structure following the additional partial adjustment, that is ;
• the difference between the first two quantities, representing the uncertainty resolved by the partial adjustment, ;
• the partial resolution, ;
• , where here is the belief structure adjusted by the belief structure .