[MWSVette]

  Statistics are useful to predict mass preference, but they are meaningless to illustrate individual choice.

+2 Well said...

 

[StanD]

  Statistics are useful to predict mass preference, but they are meaningless to illustrate individual choice.

Of course there are certain limits that no human being can exceed.

 

[SunByrne]

Warning: This is going to get technical. If you're not interested in statistics, just go ahead and skip this one.

As I understand it, CLT says if every test subject has a random (or the same) chance of getting it right every time a choice must be made, then you will get a normal distribution of test subject performance. If you have a deviation from the normal distribution, it may be significant. Am I wrong about this?

That's not actually what the CLT says—the CLT is actually pretty complicated. What the CLT says is that if you are randomly sampling from a population, the sampling distribution of the mean will approach a normal distribution with parameters that are a function of the mean of that population, the standard deviation of that population, and the sample size. This will be true regardless of the shape of the population—as long as the sample size is large enough, the population need not be normally distributed, but the sampling distribution will be.

What makes this complicated is that the notion of "the sampling distribution of the mean" is itself not a simple idea. Most of my grad students really struggle with this concept at first, so unless people really want a seriously long post, I'm not even going to attempt it here.

What it sounds like you're talking about is not actually the CLT, but the normal approximation to the binomial. When responses are independent and binary with a stable probability, the outcomes are described by the binomial distribution. If the sample size is large (say, > 30 or so), then (almost) nobody actually uses the binomial distribution, they approximate it with the normal.

The way that the Clarkson test and the Atkinson amplifier test panned out, you got a normal distribution,

A normal distribution of what? I apologize but I don't remember the details of these tests.

but only the audio reviewers and industry professionals scored full or near full marks, as a whole the results were basically normally distributed. That SHOULD have signified to the testers that there is a correlation between training and performance, that the population is not equal and that the normal distribution, might not mean that test score is random.

I'm lost. It's possible to construct a statistical model where "experience" is a predictive factor, and then test it. If this wasn't what was done, it's very hard to justify such a conclusion based only on the descriptives of the shape of the outcome distribution.

However Clarkson told the people who scored full marks or close to full marks, no they really can't hear it, they were just the "lucky coins" in the population that by accident got the answers all right, as the normal distribution still held.

Maybe. Depends on how they ran the test. In principle, if you test 100 people, you would expect to reject the default null on 5% (or whatever your alpha leve is) of those people. However, this is a well-understood problem and there are similarly well-established ways to correct for this.

In this case and I should have been more specific about this, using JUST the presence of a normal distribution, is not adequate to say that the test shows that nobody can hear the difference in amps...

That certainly sounds right. The claim that "on average, people don't hear a difference" is very different, statistically, from "nobody hears a difference."

My example pointed out ONLY that the standard deviation in objectively measured performance is as absurd as using the average 100m sprint times to say that people can only run the 100m sprint in x seconds, the other results are just by chance.

Hmm. The use of the "just by chance" phrasing in statistics is usually an indicator of the tenability of a conclusion based on some hypothesized overall population parameter (usually a mean). The presence of extreme values doesn't tell you anything about the stability of the individual measurements, only the population mean. If anybody is trying to draw conclusions about the prevalence of extreme values based on a hypothesis test of the mean, well, yeah, that's almost certainly wrong.

So if you are going to use normal stats, you better ask the right question - which is one of the harder things to do,

Truer words were never written! Though I'd modify that to "any" stats, not just "normal" stats. Most of the scientific manuscripts I reject when I peer review, I reject on the basis of incorrectly performed statistical analyses. This is indeed hard, and the complexity of the issues involved are really easy to not fully appreciate, even for people who do this kind of thing for a living.

or you have to test and re-test those performing well - if that corresponds to some factor that may prejudice their scores - to confirm they do in fact score differently than the rest of the population.

If you want to test "does this specific subgroup score differently, on average, than this other subgroup?" that's actually pretty easy to test, assuming adequate sample size. However, asking "are there specific individuals in the distribution who score in a way that is systematically deviant from everyone else?" is much harder.

What I also do not mean to say is that everybody should buy the most expensive DAC, AMP, Cables they can afford, cause they WILL hear a difference.

Again, I heartily agree!

 

[Koolpep]

  Of course there are certain limits that no human being can exceed.

Yes. But where are they and how was it condcluded? If you are talking about the average human being or any single individual? The average person cannot run 100m in under 10 secs. But it would be wrong to assume that nobody can, since some do. In lab tests some people could hear as low as 12Hz - so the 20Hz-20kHz is just a common accepted limitation but there are exceptions. Statistically there will be quite a few outliers - how far above and below the frequencies will be - who knows...

 

[sparkofinsanity]

 
Yes. But where are they and how was it condcluded? If you are talking about the average human being or any single individual? The average person cannot run 100m in under 10 secs. But it would be wrong to assume that nobody can, since some do. In lab tests some people could hear as low as 12Hz - so the 20Hz-20kHz is just a common accepted limitation but there are exceptions. Statistically there will be quite a few outliers - how far above and below the frequencies will be - who knows...

http://people.xiph.org/~xiphmont/demo/neil-young.html
 
"Auditory researchers would love to find, test, and document individuals with truly exceptional hearing, such as a greatly extended hearing range. Normal people are nice and all, but everyone wants to find a genetic freak for a really juicy paper. We haven't found any such people in the past 100 years of testing, so they probably don't exist. Sorry. We'll keep looking."

 

[reddog]

http://people.xiph.org/~xiphmont/demo/neil-young.html

"[COLOR=333333]Auditory researchers would love to find, test, and document individuals with truly exceptional hearing, such as a greatly extended hearing range. Normal people are nice and all, but everyone wants to find a genetic freak for a really juicy paper. We haven't found any such people in the past 100 years of testing, so they probably don't exist. Sorry. We'll keep looking."[/COLOR]

I have been tested several times and the doc said I was a mutant for how well I heard sounds and would like to send me to a cognitive hearing institution, to classify the range of my hearing. I would do it, if not for my mom and her illness.

 

[StanD]

I have been tested several times and the doc said I was a mutant for how well I heard sounds and would like to send me to a cognitive hearing institution, to classify the range of my hearing. I would do it, if not for my mom and her illness.

They'll experiment on your Schiit and turn you into a lab rat, be suspicious.

 

[reddog]

They'll experiment on your Schiit and turn you into a lab rat, be suspicious.

Yes the one cognitive school was linked to the military. I most likely will not go to a cognitive institute and be a gov test dummy.

 

[45longcolt]

Isn't this thread getting a bit OT, statistically speaking?

 

[JohnnyCanuck]

 
Isn't this thread getting a bit OT, statistically speaking?

 
+1

 

[DarthFader]

There are some serious issues with the way the ABX crowd draws conclusions from statistics—most critically, a failure to reject the null does not justify concluding that two things are equivalent (you basically can never "prove" two things are the same; you can only "prove" differences)—but what you're talking about here is not one of them. …
 

 
Thank you. Just, thank you. I've been trying to get this through various peoples' heads and sometimes it feels like an utterly Sisyphean task.

 

[StanD]

 
Isn't this thread getting a bit OT, statistically speaking?

It's still within the standard deviation. When you're talking Schiit, you can expect plenty deviation.

 

[tonykaz]

5 Years, 
 
Hmm, I've been a Schiit fan for 3 years now, has it been that long? 
 
Well, at this Show a two channel vinyl reviewer said this about Schiit/Hifiman : "more vivid, detailed and considerably more exciting than any of those Giant Boxes were conjuring upstairs".    Herb Reichert of Stereophile/Analog Planet 
 
You are getting some notice from the Fat Old Geezer ( FOG ) group of Edison Players that Levi & Beers had opening the Show.  
 
Still, if I were your Bean Counter, I have to say that if you spent $10 Grand on this show you're wasting your money although folks are saying you had a great presence ( hada take a ton of work to be as good as people said your tables were ).  
 
But if you don't do these shows people will think something's wrong at Schiit Headquarters; you should be there, one way or another! 
 
You might just have a "Guess what the next new Schiit product will be" contest , people put a note in a big Jar and get a prize when the new gets released if they guessed correctly. Maybe let em guess the name too but these are silly girly things to do.  
 
Tyll's videos show an exciting event, the World see's "The Show" thru his Camera's lens, it looked good to me.  
 
Overall, 2-Channel is only a Subset of the much larger world of folks wearing little white wires holding a digital device.  The Giants ( Apple & Beats ) don't do 2-Channel Shows, yet they are present at all the "Personal Audio" events.  
 
2-Channel is now kinda like an Old Geezer Hot Rod Show; sit down in your folding lawn chair with a remaining aficionado.
 
I don't know where 2-Channel is now-a-days but we've moved on.
 
Adios,
 
Tony in Michigan

 

[Koolpep]

http://people.xiph.org/~xiphmont/demo/neil-young.html

"[COLOR=333333]Auditory researchers would love to find, test, and document individuals with truly exceptional hearing, such as a greatly extended hearing range. Normal people are nice and all, but everyone wants to find a genetic freak for a really juicy paper. We haven't found any such people in the past 100 years of testing, so they probably don't exist. Sorry. We'll keep looking."[/COLOR]

Define "genetic freak"? What are they looking for?

Hearing as low as 12 Hz has been well documented in auditory research. I am not talking about super humans, just people that can hear slightly outside 20-20.

 

[sparkofinsanity]

Define "genetic freak"? What are they looking for?

Hearing as low as 12 Hz has been well documented in auditory research. I am not talking about super humans, just people that can hear slightly outside 20-20.

I think you should read the whole link.