Dear all,
I was recently writing a paper about threshold estimation in hearing and at some point I stopped.
Let suppose you are estimating a frequency discrimination threshold with a classic 2-down 1-up staircase rule (Levitt, 1971). Theoretically, you could approach the threshold from below or from above, I repeat this every year to 1st year students when I teach them the method of limits! In practice, however, in psychoacoustics we rarely-to-never approach the threshold from below.
Is there any reason for this "tradition"? I know the psychometric function should be symmetric below and above threshold! But this does not explain the "tradition"!
All the best from "it is almost winter" North East Italy.
m