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Overcoming the Perception Problem
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post Oct 8 2012, 19:21
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I've noticed an increase in forum debate about the validity of transferring the credibility of ABX from the physical domain to perception testing. I'm wondering if anyone has found a way past this issue?

The purpose of blind testing is to subtract subjectivity from the effect of - for instance - a drug trial: to assess a medication's impact on a subject's physiology with interference from their psychology. But what about when the purpose of a test is subjective perception? How do we then subtract the effect of the method to arrive at a meaningful outcome?

While we would like to remove expectation bias from the equation, if the conditions under which this is done also change the perceptive state of the listener, the test is invalidated as surely as they would be by tissue sample contamination.

Recent large scale public experiments by Lotto Labs (http://www.lottolab.org/) demonstrated that perception acuity is dramatically altered by test conditions: for instance, that time contraction/dilation effects are experienced when exposed to colour fields. In one experiment, two groups were asked to perform an identical fine-grained visual acuity test. One group was pre-emptively 'manipulated' by filling in a questionnaire designed to lower their self-esteem. This 'less confident' group consistently performed worse on the test that the unmanipulated one: their acuity was significantly impaired by a subtle psychological 'tweak' that wasn't even in effect during the test.

It seems undeniable that the much grosser differences between the mental states of sighted and 'blind' listening - considered generously - cast serious doubt on the results thus obtained.

The harder line is that blind perception tests are a fundamental misappropriation of methodology. In psychology it's axiomatic that for many experiments the subject must be unaware of the nature of the test (see Milgram). If a normalised state is not cunningly contrived, results are at best only indicative of what a subject thinks they should do; at worst, entirely invalid.

Probing hearing, the point is that a test must not change the mental state of the listener.

The contrast between outcomes of sighted and listening tests is as stark as those demonstrating suggestibility (see McGurk), but giving too much credence to such an intrinsically unsound experimental approach (not spotting this difficulty) does no favours to our credibility at all.

The only way past the dilemma seems to be direct mechanical examination of the mind during 'normal' listening to explore why the experiences of sighted and unsighted listening differ. This seems to be an interesting question.

In the meantime, the idea that - despite the method problem - results from blind ABX are valid is at least supported by the majority of data derived from home testing, Audio DiffMaker et al, so we needn't get hung up on it.
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googlebot
post Oct 11 2012, 21:44
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While the OP's reasoning and claimed inference from his cited studies are certainly flawed, he touches a valid point: Double-blind testing of isolated senses puts a subject into an artificial mode of perception, that is different from our usual perception of the world, which is always a multisensory blend. It should also be out of question, that the human brain makes excessive use of inter sensoric correlation while forming a consolidated mental representation of the outside world.

An ABX test can tell you, what an attentive mind, with artificially blocked non-auditory senses, can differentiate at best through the remaining, isolated auditory channel. I do not question, that this is probably as objective as it can get, when the auditory channel alone is all you want to map. I do question how much can be inferred regarding to the experience of actual listening situations in peoples' homes, where not only other senses (seeing your carefully composed system), but also a history of attached memories, associations and whatnot are constantly part of your perception of the world. I'm not claiming that aiming to be objective in a subjective environment is senseless, but it certainly might also make sense, that well situated, older men write magazines for each other, reporting about their experiences of trying to transform their surplus of dollars back to some sense of meaning. Subjective prose, that isn't castrated by some blinded, pain-in-the ass protocol as ABX, might be an actually more "objective" guide to identify an perfectly matching audio system for a member of any common enough group of individuals.

Long term HA usage might turn your mind into something, that has become unable to extract joy from owning expensive audio gear. A history of personal ABX comparisons can attach enough associations, so that this road is just closed. Not everyone might like that and I have come to a point, where I think that both is fine. I do also have come to the belief, that a man convinced that his gold cables sound better in a sighted test, even when he is unable to verify the same results blindly, is probably not lying to us.

PS & BTW Could it be shown already that results from double-blind listening tests correlate with the results of sighted tests over a large enough pool of listeners and different setups?

This post has been edited by googlebot: Oct 11 2012, 22:24
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krabapple
post Oct 12 2012, 06:59
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QUOTE (googlebot @ Oct 11 2012, 16:44) *
While the OP's reasoning and claimed inference from his cited studies are certainly flawed, he touches a valid point: Double-blind testing of isolated senses puts a subject into an artificial mode of perception, that is different from our usual perception of the world, which is always a multisensory blend.


Except, DBT doesn't do that.
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googlebot
post Oct 12 2012, 21:44
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QUOTE (krabapple @ Oct 12 2012, 07:59) *
Except, DBT doesn't do that.


Why do sighted test regularly lead to different results, then? Just calling it "bias, that should be eliminated" doesn't change the fact.

Imagine the following test setup: A test subject is presented music supposedly sourced from either a Sansa Clip or his favorite Burmester rack. You present an expensive looking switch to him, that's basically a dummy and that only inserts a small pause, but connects to the Clip at all times. Now imagine, you'd get a statistically significant result, that the subject rates the sound quality consistently higher, when he believes it to be coming from his Burmester rack / not coming from the Sansa Clip.

Now do a second test, this time double blind with both sources actually connected. Imagine the subject now fails to identify a difference.

What can we draw from this, especially when the subject was a honest type, sincerely motivated to rate the quality exactly as he perceived it in the first setup, without trying to prove or defying anything?

First, HA habit, the subject should stop claiming, that his Burmester setup sounds better than a Sansa Clip, as proven by the DBT. HA usually stops here.

But maybe one shouldn't. The belief, that sound was coming from a impressively crafted sound system, was able to significantly alter the subjects perception. In addition, the subjects usual mode of listening is reflected much better in the first setup than in the second (DBT).

This post has been edited by googlebot: Oct 12 2012, 22:04
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Posts in this topic
- item   Overcoming the Perception Problem   Oct 8 2012, 19:21
- - Soap   You appear to be confused. Despite common shortha...   Oct 8 2012, 19:38
- - item   To rephrase: what, in any trial, is blind testing ...   Oct 8 2012, 19:52
|- - Soap   QUOTE (item @ Oct 8 2012, 14:52) To rephr...   Oct 8 2012, 19:59
|- - item   QUOTE (Soap @ Oct 8 2012, 19:59) QUOTE (i...   Oct 8 2012, 23:32
|- - item   Part of Beau Lotto's 'Public Perception pr...   Oct 9 2012, 00:30
||- - Porcus   QUOTE (item @ Oct 9 2012, 01:30) Part of ...   Oct 9 2012, 10:53
||- - item   QUOTE (Porcus @ Oct 9 2012, 10:53) You ca...   Oct 9 2012, 12:23
||- - Porcus   QUOTE (item @ Oct 9 2012, 13:23) This for...   Oct 9 2012, 16:04
|- - krabapple   QUOTE (item @ Oct 8 2012, 18:32) Partly, ...   Oct 9 2012, 03:51
|- - item   QUOTE (item @ Oct 8 2012, 18:32) Although...   Oct 9 2012, 11:14
- - DVDdoug   I just don't see how making a good scientific ...   Oct 9 2012, 00:59
- - greynol   @item: Perhaps you could share with us a little ab...   Oct 9 2012, 04:54
|- - Porcus   QUOTE (greynol @ Oct 9 2012, 05:54) a fai...   Oct 9 2012, 09:57
|- - item   QUOTE (greynol @ Oct 9 2012, 04:54) @item...   Oct 9 2012, 11:42
|- - 2Bdecided   QUOTE (item @ Oct 9 2012, 11:42) Positive...   Oct 9 2012, 14:15
||- - item   QUOTE (2Bdecided @ Oct 9 2012, 14:15) QUO...   Oct 9 2012, 14:37
||- - 2Bdecided   QUOTE (item @ Oct 9 2012, 14:37) Deprived...   Oct 9 2012, 17:43
|||- - item   Sorry - been away, but lots of noise (most - fasci...   Oct 19 2012, 17:34
||- - dhromed   QUOTE (item @ Oct 9 2012, 15:37) 'Kno...   Oct 9 2012, 19:11
|- - greynol   QUOTE (item @ Oct 9 2012, 03:42) QUOTE (g...   Oct 9 2012, 22:07
|- - item   QUOTE (greynol @ Oct 9 2012, 22:07) @item...   Oct 19 2012, 18:33
- - hlloyge   The only people I know of to shun DBT method of te...   Oct 9 2012, 12:35
|- - item   QUOTE (hlloyge @ Oct 9 2012, 12:35) The o...   Oct 9 2012, 13:25
|- - hlloyge   QUOTE (item @ Oct 9 2012, 14:25) The sole...   Oct 9 2012, 13:54
||- - item   QUOTE (hlloyge @ Oct 9 2012, 13:54) The o...   Oct 9 2012, 14:09
|- - Canar   QUOTE (item @ Oct 9 2012, 05:25) I think ...   Oct 9 2012, 17:09
|- - krabapple   QUOTE (item @ Oct 9 2012, 08:25) The sole...   Oct 10 2012, 01:25
|- - item   QUOTE (krabapple @ Oct 10 2012, 01:25) QU...   Oct 19 2012, 18:45
|- - Porcus   QUOTE (item @ Oct 19 2012, 19:45) QUOTE (...   Oct 19 2012, 19:22
|- - 2Bdecided   QUOTE (item @ Oct 19 2012, 18:45) Certain...   Oct 22 2012, 12:53
- - aethelberht   What I can perhaps maybe possibly gather from your...   Oct 9 2012, 13:17
|- - item   QUOTE (aethelberht @ Oct 9 2012, 13:17) W...   Oct 9 2012, 14:01
|- - aethelberht   "A negative means - equally - either a) the t...   Oct 9 2012, 14:14
|- - Arnold B. Krueger   QUOTE (item @ Oct 9 2012, 09:01) DBT is d...   Oct 9 2012, 14:53
|- - hlloyge   QUOTE (item @ Oct 9 2012, 15:01) Abstract...   Oct 10 2012, 21:04
|- - Porcus   QUOTE (hlloyge @ Oct 10 2012, 22:04) If y...   Oct 11 2012, 14:20
|- - hlloyge   QUOTE (Porcus @ Oct 11 2012, 15:20) Ehem ...   Oct 12 2012, 14:26
|- - Porcus   QUOTE (hlloyge @ Oct 12 2012, 15:26) QUOT...   Oct 12 2012, 15:04
|- - hlloyge   QUOTE (Porcus @ Oct 12 2012, 16:04) Not n...   Oct 12 2012, 22:14
|- - greynol   QUOTE (hlloyge @ Oct 12 2012, 14:14) I am...   Oct 13 2012, 14:25
|- - hlloyge   QUOTE (greynol @ Oct 13 2012, 15:25) QUOT...   Oct 14 2012, 13:35
|- - Porcus   QUOTE (hlloyge @ Oct 14 2012, 14:35) Yes,...   Oct 14 2012, 23:31
|- - hlloyge   QUOTE (Porcus @ Oct 15 2012, 00:31) QUOTE...   Oct 16 2012, 09:54
- - Porcus   While I certainly agree that putting humans in a l...   Oct 10 2012, 13:09
- - 2Bdecided   It's like The Princess and the Pea. Audiophile...   Oct 11 2012, 11:58
- - skamp   If ABXing negatively alters one's ability to h...   Oct 11 2012, 14:28
|- - krabapple   QUOTE (skamp @ Oct 11 2012, 09:28) If ABX...   Oct 11 2012, 18:24
|- - mzil   QUOTE (krabapple @ Oct 11 2012, 13:24) QU...   Oct 15 2012, 17:14
|- - krabapple   You're right that different terms apply when w...   Oct 15 2012, 20:51
- - greynol   I believe our skeptic has flown the coop.   Oct 11 2012, 16:17
- - dhromed   Not everyone is as much a netizen as most of us. P...   Oct 11 2012, 17:05
- - googlebot   While the OP's reasoning and claimed inference...   Oct 11 2012, 21:44
|- - [JAZ]   QUOTE (googlebot @ Oct 11 2012, 22:44) Do...   Oct 11 2012, 22:37
||- - bandpass   QUOTE ([JAZ] @ Oct 11 2012, 22:37...   Oct 12 2012, 06:44
|- - sld   QUOTE (googlebot @ Oct 12 2012, 04:44) Lo...   Oct 12 2012, 03:38
|- - krabapple   QUOTE (googlebot @ Oct 11 2012, 16:44) Wh...   Oct 12 2012, 06:59
||- - googlebot   QUOTE (krabapple @ Oct 12 2012, 07:59) Ex...   Oct 12 2012, 21:44
||- - Nick.C   QUOTE (googlebot @ Oct 12 2012, 21:44) Th...   Oct 12 2012, 21:51
|||- - googlebot   QUOTE (Nick.C @ Oct 12 2012, 22:51) Is th...   Oct 12 2012, 21:58
|||- - Nick.C   QUOTE (googlebot @ Oct 12 2012, 21:58) Ye...   Oct 12 2012, 22:21
|||- - googlebot   I do not see how calling the phenomenon "prec...   Oct 12 2012, 23:43
||- - krabapple   QUOTE (googlebot @ Oct 12 2012, 16:44) QU...   Oct 13 2012, 22:05
|- - 2Bdecided   @Porcus: QUOTE (googlebot @ Oct 11 2012, 21...   Oct 12 2012, 10:08
|- - Arnold B. Krueger   QUOTE (googlebot @ Oct 11 2012, 16:44) Co...   Oct 16 2012, 15:51
- - greynol   I would be careful not to limit the word perceive....   Oct 11 2012, 22:58
- - greynol   I extract all the joy I could ever need from simpl...   Oct 12 2012, 06:11
- - Porcus   Among my friends, we have been blind testing ... h...   Oct 12 2012, 09:30
- - dhromed   But is there a problem?   Oct 12 2012, 22:12
- - AndyH-ha   The sighted test difference is not coming from the...   Oct 13 2012, 03:32
|- - greynol   QUOTE (AndyH-ha @ Oct 12 2012, 19:32...   Oct 13 2012, 14:16
- - Nick.C   @googlebot: You are now allowing the results to be...   Oct 13 2012, 09:43
- - 2Bdecided   I think Googlebot is making a valid philosophical ...   Oct 15 2012, 12:20
|- - pisymbol   QUOTE (2Bdecided @ Oct 15 2012, 07:20) I ...   Oct 15 2012, 13:48
- - skamp   QUOTE (mzil @ Oct 15 2012, 18:14) B. The ...   Oct 15 2012, 22:49
|- - krabapple   QUOTE (skamp @ Oct 15 2012, 17:49) What g...   Oct 16 2012, 03:58
- - greynol   There are ways of cheating to get positive ABX res...   Oct 15 2012, 22:57
- - mzil   [Trying to bring this back on topic] There is not...   Oct 16 2012, 04:32
|- - Woodinville   QUOTE (mzil @ Oct 15 2012, 20:32) [Trying...   Oct 16 2012, 04:33
|- - Porcus   QUOTE (mzil @ Oct 16 2012, 05:32) Here...   Oct 16 2012, 06:19
- - mzil   Please enlighten me. I am not a scientist nor have...   Oct 16 2012, 04:39
|- - krabapple   QUOTE (mzil @ Oct 15 2012, 23:39) Please ...   Oct 16 2012, 22:28
|- - mzil   QUOTE (krabapple @ Oct 16 2012, 17:28) QU...   Oct 17 2012, 00:30
|- - saratoga   QUOTE (mzil @ Oct 16 2012, 19:30) So even...   Oct 17 2012, 03:03
||- - mzil   QUOTE (saratoga @ Oct 16 2012, 22:03) QUO...   Oct 17 2012, 05:35
||- - saratoga   QUOTE (mzil @ Oct 17 2012, 00:35) Sorry, ...   Oct 17 2012, 05:43
|- - krabapple   QUOTE (mzil @ Oct 16 2012, 19:30) QUOTE (...   Oct 17 2012, 04:53
||- - mzil   QUOTE (krabapple @ Oct 16 2012, 23:53) QU...   Oct 17 2012, 06:36
||- - mzil   QUOTE (krabapple @ Oct 16 2012, 23:53) Do...   Oct 17 2012, 07:22
|||- - mzil   QUOTE (mzil @ Oct 17 2012, 02:22) QUOTE (...   Oct 18 2012, 19:16
||- - Arnold B. Krueger   QUOTE (krabapple @ Oct 16 2012, 23:53) Do...   Oct 18 2012, 14:04
|- - Porcus   QUOTE (mzil @ Oct 17 2012, 01:30) QUOTE R...   Oct 17 2012, 18:51
- - knutinh   Self-reporting about ones mental state surely carr...   Oct 16 2012, 21:02
- - greynol   Let me get this straight, the subconscious mind is...   Oct 17 2012, 05:28
- - mzil   Thanks, Porcus. I'll check it out.   Oct 17 2012, 20:14
- - krabapple   It's best to be careful drawing conclusions fr...   Oct 19 2012, 17:53
|- - 2Bdecided   QUOTE (krabapple @ Oct 19 2012, 17:53) It...   Oct 22 2012, 12:49
- - AndyH-ha   I could be missing the point, or dozens of them, b...   Oct 19 2012, 20:56
|- - Arnold B. Krueger   QUOTE (AndyH-ha @ Oct 19 2012, 15:56...   Oct 19 2012, 21:30
- - AndyH-ha   My point was not that many reported tests involve ...   Oct 19 2012, 22:31
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