A single input matrix file should be provided to the Analyst Drive program. The matrix input file will define the proper ordering of the user classes being estimated, and consequently the order for the listing of screenline and ICP files that must be followed in the control file or the Application Manger diagram block. When using confidence matrices, they must be contained in the same matrix file, and the tab number of the confidence matrix should immediately follow the corresponding OD matrix tab number. As a simple example, if there are two user classes and confidence matrices are to be included in the input matrix file then the first tab of the OD matrix file would correspond to the OD matrix of user class one, the second tab to the confidence matrix corresponding to the first OD matrix, the third tab would be the OD matrix for user class two and then the fourth tab would correspond to the confidence matrix for user class two. When using the CONFMAT=T option, all OD matrices must have a confidence matrix. Note that one can include confidence matrices with input OD matrices but choose not to use them in the estimation process by selecting the USECONF=F option.