S888Wheel wrote:
You are talking about misdirection.

Yes, as *one kind* of prior knowledge...the most extreme kind.


And being the most extreme kind it is likely to wrought the most extreme kind
of results.


Even if less extreme kinds yield 'less extreme' results ...which is not
conceded...do you agree that prior knowledge still biases sighted
comparison to some degree?


Yeah people are suseptable to misdirection.
One could say that sameness in components could also be imagined if the
listener believes ahead of time that no difference exists.

One could imagine that, but perceptual psychology says the stronger
tendancy is to experience *difference*.


I would like to see a citation of any study in perceptual psychology that
suggests this is true. I'll bet if it has been studied the studies would show
the pre-existing bias would prove far more powerful than any universal tendency
to percieve a difference. People, by and large, go through life not noticing
differences that do exist every bit as much as they percieve differences that
don't exist.


I wold like to see a citation of any study in perceptual psychology that
suggests this is true.

But like coincidences vs. noncoincidences the failure to note
small but real differences in our sensery perception goes largely unnoticed.

Not when a person is comparing two things. There, the tendancy is to
report difference...perhaps it's of a piece with the 'coincidence' thing,
where peopel tend to impart *meaning* to things merely based
on temporal proximity or some other possibly spurious 'connection'.
IIRC such errors of judgement are covered in the book
Inevitable Illusions : How Mistakes of Reason Rule Our Minds
by Massimo Piattelli-Palmarini, a professor of cognitive science at UAZ.



That means every ABX
DBT that has been done with people who believe no difference exists
between the components in question is tainted with expectation bias unless
a control was
used in the test for that bias such as the random insertion of a known
barly
audible distortion.


Again, 'expectation bias' isn't necessarily conscious expectation...

I don't believe that. Claims of the effects of the "subconscious" mind on the
conscious mind are highly debated. If you can cite any scientific claims that
"subconscious" biases are at work in the effects of expectation bias I'd like
to read about it. I am betting that none of the studdies on the effects of
expectation bias make any claims that the expectation bias is subconscious.


it's not a matter of going into the test, saying to yourself, I *will*
hear a difference.


I think it very much is. That is why I think deliberate misdirection is an
obvious flaw in testing for normal expectation bias. The deck is stacked.

Scott, controlled comparison for audible difference does not usually
involve *deliberate misdirection*, so please abandon this straw man
argument immediately. I merely used that example as a pretty foolproof way
to highlight the inherent tendency towards *hearing* difference when some
other sort of difference exists (either real or imagined).


And, too, when are ABX tests performed to test a claim of 'no difference'?

Every time Tom does such a test.

When has Tom tested a claim of *no difference*, rather than a claim of
*difference*?

All the ones I've sen reported involved people who claimed they could
hear a difference between A and B; if not, there would be no point in
continuing the test.

You are not a reference for recording all such tests.

You aren't a reference for scientifically-founded ideas. It doesn't stop
you from proclaiming your lack of belief in them as if it were some sort of
dispositive argument.


Do you think you know what orange juice or
cola or strawberry jello taste like? I bet you cannot successfully
identify
such items by taste alone on a reliable basis.

I'd require taste and smell, most likely. ANyone who's had a cold knows
that a stuffed nose reduces taste sensitivity. And that's been confirmed
medically, and the anatomical basis is known.

I figured that was understood. I was refering to literal blindfolding. Try it
with amny differnt samples and see how well you do.

We aren't talking about literal blindfolding of ABX /DBT testees, ever.
We aren't talking about blocking any of the senses.


Take the testee out of the
envirement and all bets are off on sensitivity.

No, Scott. All bets aren't off. We know that certain
changes to the environment reduce sensitivity. Others could
be expected to have little or no effect. This stuff has
been studied.

I am sure it has been studied. I am not so sure it has been accurately reported
on RAHE.

See above re : dispositive arguments. OF cousre, you could always do what
has been suggested many times to you: take the time to go do the research
in your local university library to your own satisfaction, and report back
to us.

Piatelli-Palmarini's book, btw, is avaialble cheaply from amazon.com


The interaction of senses is
complex and critical in sensitivty of the senses.

In some cases, for some senses, yes.

But *that's beside the point anyway*. We're not talking about blocking
any of the senses. It's not analogous to stuffing someone's nose and
asking them to identify a flavor. We aren't talking about blindfolding the
testee.
or dong the test in the dark. We aren't damping down the sense of sight.
We are only talking about keeping the identity unknown at the time of actual

listening. You can *SEE* both devices
under test, during the test, if you like. You just can't *know* which
one is playing. How could that possibly be construed as changing the
interaction of the senses?

I was talking about deliberate misdirection.

Deliberate misdirection doesn't necessarily involve hindering any senses.

If two cables or amps or CD players -- for giggles, let's make one a
hgih-end brand and the other a mass-market brand -- are hooked up to a
switchbox, with the switch and the components *always in view*, and the
proctor says the 'up' position opf the switch is DUT A and the 'down'
position is DUT B, when in fact both positions are DUT A, it's an
excellent bet that the golden ear testee will hear big differences between
the switch positions. Where have any of the senses been thwarted in this
deliberate misdirection protocol?


--

-S.

"They've got God on their side. All we've got is science and reason."
-- Dawn Hulsey, Talent Director