Wining about the placebo effect - Page 4

Quote:

Originally Posted by xnor 

So you are for blind listening tests?

 

 

To those that don't know this illusion and take a quick look: A. If you take a close look though or already know the truth ... neither.

This is an argument for blind tests right?

1. Personally, I'm neutral towards blind testing. I see some value in them, but I also see an issue with creating a special context for testing 

that doesn't replicate how we encounter things in the everyday world. 

2. This is an interesting statement. Despite knowing that the two squares measure the same in the original optical illusion, I can't get around 

how they appear in my consciousness as two different shades of grey. Doesn't matter how long I look. It's only by blocking out the context

that I can see them as the same. Remove the block and the illusion returns to my perception. 

Quote:

Originally Posted by scuttle 

If I throw a brick at your head, the impact will be the same whether I tell you it is a feather or a kryptonite ingot.

 

 

 

My friend had no reason to associate our friendship with "Wow - the HD25s sound good." The context wasn't "What do think of these?" but "What do you think of this album I've found?" And the HD25s certainly don't look like expensive audio hw and so wouldn't cue him to high expectations that way - I think most people would guess them at the price of PortaPros. So, again, real differences in sq do jump out in blind testing, making the fact that others do not survive blind test significant. 

 

Bottom line: your claim that people will only hear extra sq from high end hw if they can see the cabinets, know the brands, and are not being tested, is junk.

 

1. The brick at my head impact is a physical event. The perception of sound is a phenomenological event that presents itself to our consciousness awareness. As this discussion started with the term placebo it should be pointed out that the placebo effect (in medicine) is dependant exactly on disguising the nature of the administered treatment. So, in speaking of the placebo effect it has been shown that the impact of "brick at my head" is dependant exactly on what is told about the brick.

2. My contention is that we experience the world always inside a particular context, we don't (and possibly can't) know all the things that influence and shape our experience. Blind testing exists to bracket out many of the influences of the world in an attempt to reduce bias. Your interaction with your friend isn't free of bias and influence on his perception, even if you think they aren't there. To clarify, I'm saying that your friend did hear what he heard and a difference between your set up and his is probably noticeable and measurable, but the context isn't free of influence. 

3. I never made such a claim.

I'm saying that people experience the world inside of a context of meaning and relationships. We don't have the ability to opt out of being human and influenced by our context. Seeing labels, being proud of a home build, being influenced by social proof, admiring build quality, feeling the weight of something, knowing some technical aspect, or romanticism for the old all can factor into how we perceive something. We don't have the ability to take our perception out a context that both influences our perception and that we influence. 

JadeEast is saying that every impression is filtered by the mind, has some kinds of bias.  Not that these factors are solely responsible for any difference your friend heard.  (in fact, it was suggested that the difference is audible, without those factors)

Even in a double-blind test, there are lots of factors not controlled directly.  You can't wipe people's mental states clean, reset their brains and get them to listen the exact same way every time.  There will still be order effects and more.  It's just a matter of eliminating or reducing some biases and hopefully being able to randomize out the effect of anything remaining.  In a sighted test, every exposure to stimulus A will be biased by knowledge of what A is, so that kind of significant effect is tainting all the results.  Sure, different people may have different reactions to knowledge of A, but there is often still some kind of net effect.

Quote:

Originally Posted by JadeEast 

1. Personally, I'm neutral towards blind testing. I see some value in them, but I also see an issue with creating a special context for testing that doesn't replicate how we encounter things in the everyday world.

You can do a blind test at your home in your favorite chair with your music of choice etc. - in whatever context you like.

When I listen to an album I set up everything and then turn away from the amp. There's no need to look at it let alone touch it during listening. That's not far from a blind test. It's as simple as asking a friend or family member to switch between amp A and B (level matched of course).

Since some people seem to be skeptical towards scientific tests and their results they should do their own blind tests. Care needs to be taken though (level matching for example) and one has to be honest about the test procedure and results.

Let me quote Neil deGrasse Tyson:

I rather base my buying decisions on reality/facts/science than "brain failures".

Optical illusions can be as simple as this:

The upper line segment appears to be too high. If you rotate your head CCW you should see that they are aligned on a straight line, that works for me at least. No need to remove anything.

Anyway, even if an illusion could fool a person 100% of the time it would still only be a distortion of the person's senses - a distortion of reality.

Quote:

Originally Posted by scuttle 

 

Your second sentence is grammatically and semantically appalling: in attempting obfuscation you have lost the ability to convey meaning - which may well have been what you intended. Leaving aside the utter pretension of your phrasing, "the perception of sound" is a process, not an event. You should have written "The perception of ***A*** sound is a phenomenological event that presents itself to our consciousness awareness." 

 

But even then you'd deserve stoning to death for English Abuse: what is the difference between a phenomenological event and any other event? How is "conscious awareness" different to "awareness"? 

 

Indeed, wouldn't a person possessing either shame or taste simply have written "When we hear things our mind is involved as well as our ears"? This isn't any deep insight - indeed in context it is trite to the point of stupidity - but at least it is honest and clear, and pretentious and stupid is much worse than just stupid.

 

 

 

 

No, this is not your contention. This is vague bs that has no meaning so it is not a contention. It would become a contention if you had the nerve to say something definite (What part of "context" had what "influence"?) but at the point you do then you will have nowhere to hide and will look ridiculous even to yourself. Unless of course you are trying to say that the above has a significant effect all the time - in which case it is a mystery how the computer you are using works, as it is based on theory gained by experiment, which by your reasoning should be unreliable to the point of being useless.

 

 

You are now being even sillier. You are trying to claim that

 

- A sound quality that existed

 

- That was heard in an informal blind test where no cue was given to expect a difference

 

- That was so large a difference was reported even though an opinion on sq wasn't sought

 

- With no definable cues to bias expectation upwards (indeed cues were arguably negative, because HD25s look that damn cheap!)

 

..Was only heard because because of biases you can't even suggest. 

 

This is, of course, just two things: "ab" and "surd".

 

I don't like your hostile tone and choice of confrontational language. I'll come back later and address your points, but I doubt I respond to ridiculing statements that I didn't make. 

Yeah, if anything I'd argue that because optical illusions can mess with our brain visual stimuli can also change (as in distort reality) what we hear, feel ...

Doesn't even need to be visual. Reading/hearing something about a component like "it sounds warm" is enough.

Quote:

Originally Posted by xnor 

Yeah, if anything I'd argue that because optical illusions can mess with our brain visual stimuli can also change (as in distort reality) what we hear, feel ...

Doesn't even need to be visual. Reading/hearing something about a component like "it sounds warm" is enough.

It doesn't even need to be reading about something or seeing it, though those can be factors.

Some of it just has to do with a person's mood, how they are listening during their first impression, the volume set, or any number of things.  Then subsequent impressions are all influenced by the first impression, confirmation bias takes hold, etc.

I think people need to be careful when distinguishing between blind tests that are run (many of them are not run well, not suited to high statistical power to reject the null even for something that should be discernible, do not establish auditory thresholds and more) and blind tests in general, as a theory.

Suppose you set up the following experiment:

Each person takes home two boxes, one labeled A and one labeled B.  They could be amplifiers, DACs, whatever you were interested in testing, with an input and output connection.  Just a black box with something inside, but externally indistinguishable in every possible way except the audio signal passed through.  Randomize which thing goes into A box and which into B.They are asked to try out both A and B in their systems at home, on their own time.  (And in this fantasy land, they can't measure the outputs and are only evaluating things by listening to them.)  Then after a week (day? who cares), they report back which they preferred.  Repeat this many times for each person and for multiple people.  You could change what goes into the boxes, like maybe sometimes A and B are identical, to get more data.

So this is blinded in the sense that nobody knows what they are listening to, which is what we want.  How is there a disadvantage here or significant difference compared to normally using audio equipment?  Maybe there is some pressure of some kind of test, even if it is on their own time?  But it's not much different than buying a new piece of gear and trying to evaluate it, which many people do.  That's not the best experiment or one you would run, but hopefully you get the idea.

I mentioned honesty above but I guess you'd get more reliable results with such boxes. They'd also have to be the same weight and show clear signs when they were opened so that fake results can be discarded. The connectors would have to be identical and be at the same position.

In case of amps the volume would have to be controllable but matched between A and B while factoring in the output and load impedances. Phew...

Quote:

Originally Posted by scuttle 

What he is saying is that he can assume such biases will arbitrarily have any particular effect that he wants - so that blind tests will introduce some weird confounding factor that make bad and good hardware sound the same. Except when the test is of an HD25 playing Nico's "Marble Index" in an Arabic cafe, when he magically issues himself a get out of jail free card when there is an audible difference!

 

And I can't blame you for not following what he has tried to claim, because he really has been exceptionally pretentious and (I am sure deliberately) unclear in how he has expressed his ideas!

I've made no claim that a blind test introduces weird confounding factors that make good and bad hardware sound the same. I've claimed that our perception is always influenced and formed by context. The optical illusion was used as an example of perceiving things differently in different contexts.