Human Error
Endsleys model of situation Awareness
Projection of future system status
Comprehension of situation
Perception of elements in current situation
Post-completion errors
Dont fill up working memory, should be OK
photocopier, ATM machine, filling petrol
Mistakes
correct execution of incorrect action sequence
Arise from the inappropriate choice of a goal
Slips
Most errors are slipsSkilled behaviourLack of attention1 focus of attentionUnconciousEasy to uncover
Mode Error
Watch. Run. Reset
Description
Internal description of intended action not suffiently preciseUsually correct action, wrong object. e.g. OJ in bowl of cereal
Capture
Frequently done activity takes charge
1: Normans 7 Stages of Action
GULFS of execution/evaluation
Goal, Intent, Action Spec, Execution, WORLD, perception, interpret, evaluate.
framework for account for how error may arise from interactingwith technology
Reducing Errors: Screen: Undo, confirmation box, Modes, text boxes,
Reducing Errors: More Knowledge in the world: Visibility, Clues, Affordances, feedback, Mapping, forcing function