webers law

Question 1

What is luminance?

Answer 1

Quantity of light

Question 2

What is brightness?

Answer 2

Describe the apparent quantity of light

Question 3

What is a transducer function?

Answer 3

Describes how physical intensity is transformed into perceived intensity

Question 4

What is a transducer?

Answer 4

A transducer is a process whereby physical stimuli are converted into neural signals

Question 5

Who published to first book of psychopysics?

Answer 5

Gustav fechner in 19860s

Question 6

What is the dependant variable ?

Answer 6

What the psychologist measures

Question 7

what is independent variable ?

Answer 7

manipulating the data

Question 8

What is a psychometric function?

Answer 8

A figure which shows relationship between physical quantity and some measurement of behaviour

Question 9

What is noisy?

Answer 9

Observer did not always respond in same way to same stimuli

Question 10

Explain experiment of 2AFC?

Answer 10

Two alternative forced choice test

• sit in the dark
• two beeps both with two bright lights
• lights not same intensity
• one has intensity =L
• one has extra intensity = delta L
• job is to detect the brighter intensity of light

Question 11

Who came up with the wright and wrong case method?

Answer 11

Fechner

Question 12

What is another name for wrong and write cases?

Answer 12

Multiple alternative forced choice test m

Question 13

What are the two independent variable in 2AFC test?

Answer 13

baseline/ pedistal luminance =L

and extra luminance = delta L

Question 14

What would happen if Transduction was flawless

Answer 14

The brighter light would always produce more bright light

however not always flawless its noisy

Question 15

What does alot of overlapping of distribution mean?

Answer 15

The probability of incorrect responses was high correct response probability would be near 1 and half

Question 16

What does little overlapping of distribution mean ?

Answer 16

The probability of correct responses is high the less intense light will never produce,

Question 17

What does having same width on two curves mean?

Answer 17

Mild experience may be variable as intense experience

Question 18

What does average brightness vary with?

Answer 18

Average brightness varies with the logarithm of luminance

Question 19

How can you directly measure appearance?

Answer 19

You cannot it is impossible

Question 20

How do you assign a value to SD of appearance noise?

Answer 20

Indirectly

Question 21

ho demonstrated shadows?

Answer 21

Bouguers

Question 22

Describe Bouguers experiment

Answer 22

• Two candles where light reflects from both candles reflect of the paper and cast shadows of the rod in between the candle and paper
• one candle set at a fixed distance - second candle increased distance until shadow disappeared
• Far enough till shadow just noticeable difference

Question 23

What is just noticeable difference method of ?

Answer 23

Method of limits

Question 24

Noticeability is what?

Answer 24

A judgment call no wrong or right answers

Question 25

What law did Bouguers come up with and when?

Answer 25

Webers law in 1834

Question 26

What is webers law?

Answer 26

Just noticeable of physical intensity over actual physical intensity equals to arbitary constant