Psychophysics - fechner and weber
Benjamin Wallman - stimulus magnitude >> sensory experiences
Psychophysics
- systematic, scientific, reliable
- study of stimuli and their experiences
First basic question : acknowledgement of stimuli
Second basic question : minimum diff in stimulus
Third basic question : comparison error
Zimmy - experimental psychology - scientific tool in studying organisms
Direct and indirect methods
Our nervous system does not absorb all stimulus, not all stimuli can generate sensory response
The amount of the stimulus can be placed on the continuum from mild to intense. [extremes]
Limits - latin origin - limen
Minimum stimulus : 50% (presumed)
Differential threshold - just noticable difference
The stage or point at which a person feels that two stimuli are equal is called point of subjective equality.
* These stimuli may not be similar so it's an error
Rank method and paired comparison method
Individual judgement << psychophysical methods
Standard deviation - SD -
Possible errors :
Place / direction :
Eg. Muller Lyer experiment
Solution - balancing, holding it still at place on both right and left
Time / practice error -
Solution : counterbalancing
Movement error - ascending descending trail problem
Solution : ABBAABB pattern in result sheet
