SDtest musings

[From Samuel Saunders (950313:1815 EST)]

I seem to be having net sclerosis today. A post I sent last night had
still not been acknowledged earlier this afternoon. I am still getting
things posted on Sunday, a few at a time. It makes conversation a bit
difficult. Here are a few points:

Bruce Abbott (950312.1410 EST) --

I'm 49. Rick and Sam, what are your ages?

I too am 49. It looks like a popular number.

[Bill Powers (950312.1715 MST)]

Speaking of switching, however, there's one aspect of the SD that needs
investigation. On my monitor screen, the red and green colors are rather
dim (or my eyes are). There's a question as to how long a changed color
has to be present before the perceptual signal rises or falls enough to
count as a change.

I had been thinking about this also. It might be interesting to include
some much more difficult discriminations, such as a green versus
blue-green, to see what sort of an influence discriminability has. If my
post from last night ever gets out, this is one of the things I had in mind
with wondering if Luis' color blindness influenced his mean delays.

It might be interesting to look at a task in which the targets are colored
as well, and the cursor and target color are required to match. That would
perhaps move the problem up a level in the hierarchy; on the other had, it
could make things easier since the memory requirement (what goes with
green ?) is eliminated. (Of course, the task could be non-matching, or an
arbitrary pairing; that should affect acquisition but not final
performance, I would expect).

Until the kink in the ether is resolved, I suppose that should be enough
said.

//----------------------------------------------------------------------------
//Samuel Spence Saunders,Ph.D.