Principles of Perceptual Measurement II

Question 1

What are the two fundamental assumptions of Fechner’s Law?

Answer 1

Every JND feels the same The magnitude of sensation change is equal to the number of JNDs

Question 2

True/False? People are comparable in judging the sensory magnitude of their experience

Answer 2

True

Question 3

True/False? The sensory magnitude of people’s experience follows a logarithmic curve

Answer 3

False, See Steven’s Power law

Question 4

True/False? Changing motivation affects one’s ability to detect eg a sound

Answer 4

True

Question 5

What two measures are required to estimate true sensitivity?

Answer 5

Hit rate and False Alarm rate (False positive)

Perfect hits no misses < Perfect hits, no false alarms

Question 6

What does d’ represent in Signal Detection Theory?

Answer 6

The distance between the peaks of signal and noise when plotting a probability graph

Representative of stimulus sensitivity

d’ - Z(hits) - Z(False alarms)