Human error models Categorize errors by external manifestations Categorize by type of task Simple, vigilance, emergency response, control, complex Coordinating, scanning, recognizing, problem solving, planning Usually consider performance-shaping factors such as task structure, stress, design of displays and controls Categorize by cognitive mechanisms Instead of focusing on task and environment characteristics consider psychological mechanisms used by operator in performing tasks Interaction of psychological factors with features of work environment Requires only a limited number of basic concepts Common Features of Cognitive Models Most based on bartletts schemas Internal representations of regularities of the world An organized structure of knowledge Our way of understanding and dealing with world Slips vs Mistakes(Don Norman) Mistake is an error in intention(error in planning) Slip is error in carrying out the intention Human-Task Mismatch(Rasmussen) Errors are an integral part of learning Should be considered human-task or human-system mismatches Skill-Rules-Knowledge framework(Rasmussen) Human skills needed to solve problems also lead to errors If eliminate possibility of human error, may eliminate ability to solve problemsc ✎✞✝✞✏✄✝✞✍✄☛✞✟☞✑③❏✞❏❑➨ ￾✂✁✄✁✄☎✆⑤✝✞✟✞✠✞✡✵☛✞✆⑤✝✞✌✍ Human Error Models Categorize errors by external manifestations Categorize by type of task Simple, vigilance, emergency response, control, complex Coordinating, scanning, recognizing, problem solving, planning ... Usually consider performance−shaping factors such as task structure, stress, design of displays and controls Categorize by cognitive mechanisms Instead of focusing on task and environment characteristics, consider psychological mechanisms used by operator in performing tasks. Interaction of psychological factors with features of work environment Requires only a limited number of basic concepts c ✎✞✝✞✏✄✝✞✍✄☛✞✟☞✑③❏✞❏❑➩ ￾✂✁✄✁✄☎✆✞✝✞✟✞✠✞✡☞☛✞✆✞✝✞✌✍ Common Features of Cognitive Models Most based on Bartlett’s ‘‘schemas’’ Internal representations of regularities of the world An organized structure of knowledge Our way of understanding and dealing with world Slips vs. Mistakes (Don Norman) Mistake is an error in intention (error in planning) Slip is error in carrying out the intention Human−Task Mismatch (Rasmussen) Errors are an integral part of learning Should be considered human−task or human−system mismatches Skill−Rules−Knowledge framework (Rasmussen) Human skills needed to solve problems also lead to errors If eliminate possibility of human error, may eliminate ability to solve problems