For some purposes measures without any weights would be sufficient. In a voucher system for education, for example, one could simply make available a variety of performance measures for each school and let parents and students choose among them according to their own weights systems. On the other hand, in a federal grant program designed to encourage effective manpower training, it would be necessary to assign weights to the various success measures being used. If several are being combined, as no one measures is allowed to dominate and distort the reward system.