Is ‘reverse’ expectation bias a thing?

[kemmler3D]

As I’ve become more acutely aware of the evils of expectation bias I wonder if I am now suffering from something I’d call reverse expectation bias.

In my definition this is the expectation that there should be no difference in sound (even if one might exist) leading to not hearing / observing any change in sound quality.

I’m half serious / half joking here! I no longer trust my ears

Short answer: Yes. In medicine it's called the nocebo effect, basically the "bad" version of the placebo effect.

I once read a review on a homeopathic remedy, i.e. sugar pill, i.e. actually does nothing. The medical equivalent of swapping one 3-foot cable for another. The reviewer said it gave them a terrible allergic reaction and they would never take this "remedy" again. The poor thing gave themselves a bad case of 'reverse expectation bias', aka nocebo effect.

In my mind, it's a certainty that the same thing can and does happen in audio.

 

[krabapple]

Short answer: Yes. In medicine it's called the nocebo effect, basically the "bad" version of the placebo effect.

I once read a review on a homeopathic remedy, i.e. sugar pill, i.e. actually does nothing. The medical equivalent of swapping one 3-foot cable for another. The reviewer said it gave them a terrible allergic reaction and they would never take this "remedy" again. The poor thing gave themselves a bad case of 'reverse expectation bias', aka nocebo effect.

Except, this is analogous to hearing a difference when there is no difference: standard sighted listening bias. Anything labelled a 'remedy' would foster expectation of it doing 'something'.

In my mind, it's a certainty that the same thing can and does happen in audio.

Maybe , but I don't see how your example relates.

 

[kemmler3D]

Except, this is analogous to hearing a difference when there is no difference: standard sighted listening bias. Anything labelled a 'remedy' would foster expectation of it doing 'something'.





Maybe , but I don't see how your example relates.

My broader point is that expectations can modify perceptions more or less arbitrarily. Your expectations can make sound better, worse, or eliminate the perception of change entirely.

Consider that many, maybe most people can be hypnotized - in this case we're seeing "expectation bias" replace the person's reality entirely.

The fact that people hear major differences where there are none, or no differences where they are major, should be not be surprising, if a person can almost as easily be convinced they are covered in bees or can only speak backwards, or whatever they do in stage hypnosis shows.

 

[JaMaSt]

Cute video showing how animals have learned expectations about how the world should work (make inferences).

 

[Duke]

As I’ve become more acutely aware of the evils of expectation bias I wonder if I am now suffering from something I’d call reverse expectation bias.

In my definition this is the expectation that there should be no difference in sound (even if one might exist) leading to not hearing / observing any change in sound quality.

Seems to me that would just be regular old "expectation bias" (rather than a "reverse" variant): Expectation about the outcome of the event influencing the outcome of the event.

 

[CapMan]

Seems to me that would just be regular old "expectation bias" (rather than a "reverse" variant): Expectation about the outcome of the event influencing the outcome of the event.

I think that’s probably the simple truth. We hear what we want to hear based on our mental conditioning.

 

[Gorgonzola]

Reverse bias does exist but in my experience, it is a much smaller factor. To wit, many times I measure something that looks good then listen. I then notice it doesn't sound good only to find that I have an EQ enabled. I turn it off and then hear it like it is. This means reverse placebo was not powerful enough to override what I was hearing.

I marvel when I visit my favorite audiophile sites -- yes, there are still a couple I visit regularly. There is still plenty of talk about, for instance, the superiority of the this or that cable, electrical or vibration isolation devices, and the like.

I feel that many of these old-time, (and increasingly old-aged), audiophiles are becoming a bit jaded. Discussion is tending away from the above sorts of paraphernalia to components that more plausibly could have sound differences: speakers obviously, but also amplifiers and DACs. These folks are out to find differences and I do honestly believe that some of them with many decades of listening experience are, indeed, expert listeners and can detect very small differences. You might say they have a deficit of "negative expectation bias" rather than an excess "positive expectation bias". Of the latter, the most common is still that more expensive is probably better.

OTOH I feel that the negative sort of bias is pretty common here at ASR. Some members automatically and mockingly dismiss any & all assertions of differences by other members as imaginary. That is, if those sceptics auditioned various components they would tend to miss real (and actually measurable) differences.

 

[Sir Sanders Zingmore]

As I’ve become more acutely aware of the evils of expectation bias I wonder if I am now suffering from something I’d call reverse expectation bias.

In my definition this is the expectation that there should be no difference in sound (even if one might exist) leading to not hearing / observing any change in sound quality.

Interesting question. I agree with Duke that it's just expectation bias (rather than "reverse").

I find it hard to imagine that this isn't a real thing. And that means there must be some proportion of negatives in DBTs that are false.
Is there a way to work out how often it might happen or better still eliminate it?

 

[Killingbeans]

Is there a way to work out how often it might happen or better still eliminate it?

I imagine designing a test with a "negative control" component.

First do a set of baseline test on each subject to determine their hearing thresholds. Then add a repeating component to the main test that has a difference the specific subject has a high probability of detecting. If the difference is not detected, the data point should be weighted significantly lower.

Don't know whether that's already a thing. Just thinking out loud.

 

[Killingbeans]

OTOH I feel that the negative sort of bias is pretty common here at ASR. Some members automatically and mockingly dismiss any & all assertions of differences by other members as imaginary. That is, if those sceptics auditioned various components they would tend to miss real (and actually measurable) differences.

Guilty as charged. Or rather, I like to point out the probability of things. If somebody goes "This is so obvious that even my deaf old grandmother would be able to hear it", but the measurements shows artifacts with a ridiculously tiny amplitude, I simply can't keep my mouth shut.

Some people probably see that as a form of mockery, but I don't. I'm not a big fan of actual mockery.

And I definitely tend to miss real differences. Some of it is probably the result of bias, but most of it just because my hearing is absolute shite

 

[Gorgonzola]

Guilty as charged. Or rather, I like to point out the probability of things. If somebody goes "This is so obvious that even my deaf old grandmother would be able to hear it", but the measurements shows artifacts with a ridiculously tiny amplitude, I simply can't keep my mouth shut.

Some people probably see that as a form of mockery, but I don't. I'm not a big fan of actual mockery.

And I definitely tend to miss real differences. Some of it is probably the result of bias, but most of it just because my hearing is absolute shite

My hearing isn't so great either, in fact an account of my age and other factors I'm really stone deaf above 9 kHz. (But note that virtually all instrument fundamentals and many harmonics are below that frequency.)

Perhaps the even bigger factor in my case is indifference, i.e. I think I might hear a difference but it is simply too small to matter.