Human Factors 4

Question 1

Hs = Ht = Hr

Answer 1

Hs: stimulus information
Ht: information transmitted by operator
Hr= response information

Question 2

Reaction time - Hick’s Law

Answer 2

the more things you have to think about the slower the reaction time = therefore the slower you are

Question 3

Human information processing model

Answer 3

1. sensory processing
2. perception
3. memory and cognition
4. response selection & execution
5. feedback
6. attention

Question 4

sensory processing

Answer 4

convert physical energy to electrical energy and send to brain

Question 5

temporary storage

Answer 5

visual (iconic) - 100ms-500ms

auditory (echoic) 3-5 secs - requires more processing so lasts longer

Question 6

range of sensitivity

Answer 6

expressed from the smallest detectable to the largest tolerable without pain

Question 7

just-noticable difference

Answer 7

smallest diffference between two stimuli that can be detected

Question 8

working memory

Answer 8

rehersal, reasoning, or image transformation
30 sec
info actively processed

Question 9

long-term memory

Answer 9

material rehearsed in working memory can become long term memory
semantic memory , knowledge of the world, symbols, concepts
episodic memory

Question 10

perception

Answer 10

decoding the meaning of raw sensory data

Question 11

top-down

Answer 11

perception of objects based on expectation and context

Question 12

bottom-up

Answer 12

perception is based on sensory system first

you get the little sensory pieces your brain puts them together and you see the big picture

Question 13

guidlines in perception for human factors

Answer 13

max bottom-up processing
max automaticity and by using familiar perceptual representation
max top-down processing when bottom-up might be poor

Question 14

max bottom-up processing

Answer 14

high visibility, legibility, audibility

prevent confusion due to similar messages etc

Question 15

max automaticity

Answer 15

use familiar perceptual representation

familiar fonts, language , meaningful icons and symbols

Question 16

max top=down (when bottom-up might be poor)

Answer 16

max discriminating features
create context
exploit redundancy - both visual and auditory displays
use smaller vocab
be wary of possible perceptual errors

Question 17

response and execution

Answer 17

understanding is through perception then cognition will trigger a response
followed by execution - requiring motor effort

Question 18

signal detection theory

Answer 18

2 discrete states of the world are not easily discriminable

-signal present or absent

Question 19

signal detection theory

Answer 19

investigate thresholds of detection

Question 20

most likely response

Answer 20

more likely to detect a signal that is present then to detect that there is not a signal

Question 21

things that affect response

Answer 21

• context
• personality type
• risk reward or pay off

Question 22

discriminability index

Answer 22

how good you are at identifying it

low signal to noise ratio

Question 23

risk for reward

Answer 23

giving an intervention who doesn’t need it isn’t bad

but not giving the intervention to someone who is at risk then its the worst

Question 24

criteria for signal detection theory to work

Answer 24

physiological - sensory organs can pick up signal
identification - identify as a stimulus
detection - discriminate signal from the noise
recognition - correctly classify it

Question 25

sensitivity

Answer 25

true yes

Question 26

specificity

Answer 26

true no

Question 27

signal to noise ratio

Answer 27

``` high = large discriminability index low= low discriminability index ```

Question 28

positive stereotype/expectancy

Answer 28

reaction happens faster and improved quality

Question 29

negative stereotype

Answer 29

increased reaction time and decreased quality