||The intrinsic features of woker, ``ability' and ``motivation', are useful resources of human capital that makes profit for the firm.|
The purpose of the study is to examine how the firm designs the optimal wage policy when worker's intrinsic features are private information.
The study follows the mechainsm-design approach, by which models with single, as well as double,
intrinsic feature(s) of worker are established, and best ``incentive wage packages' are deduced. We finded out that, under single intrinsic feature, the firm's optimal wage package entails that, the more output the higher wages; under double intrinsic features, the firm must takes the relative strength of intrinsic features of the worker into account when making the optimal incentive wage package.