Lecture 18: Human Error (Part II)

Question 1

When following a procedure, what’re two reasons why an error may occur?

Answer 1

• Missing a procedural step
• LAX controller ‘forgot’ commuter was on runway when clearing aircraft to land
• There’s a flaw in the procedure

Question 2

Wherever tasks require a procedure to be followed, _____ and _____ are sure to follow.

Answer 2

• Slips

- Lapses

Question 3

Distraction and Interruption example:

Answer 3

• Queenstown: 2003
• Pilot fails to clip tourist to hang glider
• Two previous launches aborted

Question 4

Flaw in procedure example:

Answer 4

• ATM
• People took their cash and forgot card and receipt
• Now remove cash step is last

Question 5

ATM new procedure is less error prone because:

Answer 5

• All the actions are accomplished before the goal

- Seeing and touching card is a strong cue to next step (remove cash)

Question 6

When an interruption occurs in a procedure, three things can occur:

Answer 6

• Pick up where you left off
• Pick up one step before (fine, just means repetition)
• Skip a step

Question 7

Slips can arise due to:

Answer 7

• Faulty intention (mode error)
• Faulty activation (capture error)
• Faulty triggering (blends)

Question 8

What is mode error / faulty intention?

Answer 8

• Intention inappropriate for current situation

Question 9

Mode errors are becoming very common in ____ ____ with many functions but few _____.

Answer 9

• Complex systems

- Displays

Question 10

What is a capture error? Give an example

Answer 10

• When a familiar habit substitutes itself for the intended actions
• Put money into the coffee machine but actually wanted cigarettes
• Go into your room to change out of school uniform end up putting on pyjamas because it’s a strong habit
• One action sequence is hijacked, the other has been taken over, you find yourself carrying out a different familiar action

Question 11

What are “blends”? Give an example

Answer 11

• Two schemas triggered simultaneously

- Throwing earrings to dog, trying to put dog biscuits on ear

Question 12

What are lapses (loss of activation)?

Answer 12

• Actions continue even though intention is lost

Question 13

Slips and Lapses naturally happen with ____ _____. Slips take _____ forms. Analysis of slips give us insight into..

Answer 13

• Skilled actions
• Predictable
• How skills are organised and developed

Question 14

Stressors will…

Answer 14

• Be appraised as stressful
• Produce physiological changes
• Affect performance

Question 15

Stressors can…

Answer 15

• Improve performance

- Impair performance

Question 16

If a situation is stressful, is there difference on peripheral task under stress?

Answer 16

• Yes

Question 17

Attentional Narrowing:

Answer 17

• Reduced working memory