Signal Detection Theory Flashcards
What is the definition of a threshold?
Limit of sensitivity, smallest stimulus able detected
WIT: A method of assessing the decision making process for someone who decides between different items and their bias to favor a particular response
Signal Detection Theory
The theory of signal detection provides what?
A measure of detectability free from response bias
WIT: a scale of which people rate their psychological experiences as a function of the level of a physical stimulus
Psychophysical Scale
The underlying model of SDT consists of two normal distributions, one representing a ________and another representing ____________.
signal, noise
The difference between the signal and noise curve tells what?
- sensitivity
- how sensitive a person is to the stimulus
If a patient has a high detectibility index, it is (easier/harder) to detect stimulus?
easier
If a patient has a low detectibility index, it is (easier/harder) to detect stimulus?
Harder
This is known as a measure of strength of a signal relative to the noise
Detectibility
This has an influence on response due to costs and rewards
Response bias
This can be derived from the hit and false alarm rate
Z-score
This provides a way of measuring response bias and correcting for it
Decision theory
What eliminates response bias?
Forced choice
This is a scatter-plot which shows the relationship between false alarm rates (x-axis) and hit rates (y-axis)
Receiver Operating Characteristics (ROC)
What is the advantage of a ROC graph?
It captures all aspects of SDT in one graph
