
Lec #5 09/27/10
¥=F(ø)
-Relationship between physical and psychological to see what kind of response you get
-Types of scales
-Even if JND are physically different in size they will be psychologically the same
¥=Klogø
Stevens-psycho-physicists: Magnitude estimation: given a stimulus (brightness, length etc) saying call this
physical stimulus it ten. If twice as loud call it 10, half as loud 5 etc. Use this stimulus to give ratios.
-Numbers will truly reflect actual psychological stimulus
Power function ¥=Kø^n
Loudness Scaling
Series Standard 1 2 3
1 100 200 50 100
2 100 30 80 150
3 100 150 200 20
4 100 10 70 130
5 100 100 40 300
6 100 250 40 45
log¥=log(kø^n)
= logk + logø^n
=logk+nlogø
Y = C + nX
Cross modality matching- present to subjects a stimulus then give them control over intensity of another
stimulus to match both intensitys. e.g. match brightness with loudness