HUMAN-COMPUTER NTERACTION execution/evaluation loop goal execution evaluation system user establishes the goal ormulates intention specifies actions at interface executes action e perceives system state o interprets system state evaluates system state with respect to goalexecution/evaluation loop • user establishes the goal • formulates intention • specifies actions at interface • executes action • perceives system state • interprets system state • evaluates system state with respect to goal system execution evaluation goal