A peer-reviewed study about Wikipedia's accuracy

[EC-Bills]

It's from a top-50 school, which makes it better than whatever "Degree in a Cracker Jack box" school Ramius is currently embarrassing. And I received a more rigorous education in statistics than did Ramius. Then again, Ramius's statistics education consisted of the following classes:

 

Degree in a Cracker Jack Box U course schedule

• Statistics 101: How to parrot the phrase "correlation does not imply causation"
  
• Statistics 102: How to call other people idiots for using statistics
  

 

Top 50 in what? Universities get ranked differently on their programs. When I graduated from the University of Illinois, my program was ranked top in the nation in research. FSU's Chem and Biochem programs are ranked within the top 25 of the country.

[DC Tom]

How on earth do you think I'm guilty of "treating the behavior of the error as being behavior of the population"?

 

Uhhh...because you said error causes the population to regress toward the mean. Because you see, when you say something, and then deny you said it, the denial does not change the fact that you actually said it. It just makes you look stupid.

 

As you pointed out, I acknowledged the probabilistic error distribution is distinct from the distribution of the underlying population. Nor is this any new revelation, as you can see for yourself if you go back and look at the methodology for my Monte Carlo simulation. Initially, I created a normally distributed population. Then I gave each member an I.Q. test with an error term (mean of zero and a SD of 1/4 the amount of the SD of the population distribution). So you can stop pompously repeating that kindergarten-level phrase about things which are different aren't the same.

1) You acknowledged it today. After four MONTHS of denying it.

2) Your "Monte Carlo" simulation was not a Monte Carlo simulation. It was a numerical simulation...but not a Monte Carlo simulation. So please stop calling it that.

3) It was a piss-poor numerical simulation, because - again - you confused the distribution of individual error with the distribution of the population. THEY ARE TWO DIFFERENT THINGS, HENCE NOT THE SAME. I keep repeating that kindergarten-level phrase because you are incapable of grasping that kindergarten-level concept.

 

We both (I hope) agree that in a test-retest situation, with a normally distributed population and a normal or uniform error distribution, those who obtain extreme scores the first time around will tend to score closer to the population's mean upon being retested.

 

We absolutely do NOT agree. In a test-retest situation, the value of a measurement is established as (actual value) + (error term). In a test-retest situation, the actual value is CONSTANT, the error term is VARIABLE. Ergo, an individual measurement in a test-retest situation will only vary by the error term, which will regress toward the mean error for extreme values of error. Over a bulk population of measurements, the net error is ZERO, so it does NOT cause any regression toward the population mean. That is mathematical FACT. The reason you don't understand this concept is because you do not understand the kindergarten-level concept of THINGS THAT ARE DIFFERENT ARE NOT THE SAME.

 

The reason you mistakenly believe error is causing regression toward the population mean is because you establish a sample set of scores with a mean positive net error and discard those with mean negative net error. Your sample DOES NOT have normally distributed error. But then, when you retest, the error, being completely uncorrelated between tests, becomes normally distributed. BUT THIS IS ONLY THE BEHAVIOR OF THE ERROR TERM OF THE MEASUREMENT. When you choose your sample set of scores, you are effectively fixing the (actual value) term as a constant. Ergo, you've defined it as NOT REGRESSING TOWARD THE MEAN.

 

Your problem - again - is that you are completely incapable of distinguishing between the two distributions. A large part of the reason for this is that you're drawing on sources like Wikipedia and Hyperstats, using terms like "chance" and "luck", and failing to understand that these are not the same as error or variance. Again, you don't understand the math, so you can't see that THINGS THAT ARE DIFFERENT ARE NOT THE SAME THING.

 

You point out that this isn't because the underlying values are moving toward the population mean (they're not) but because of what's going on in that error distribution. Fine. I understand that. I've understood that from the beginning, as you can see if you go back and reread my posts.

No, you said way back in November: "I am measuring the regression of I.Q. scores. Someone who obtains a score that's far from the mean on the first test, more often than not, will get a score that's closer to the mean upon taking a second test." You specifically deny the existence of two different distributions, and claim measurement error of individual measurements and variance in a statistical distribution of measurements are identical.

 

You seem to feel that "regression toward the mean" ought to mean "regression toward the mean of error" when referring to a test-retest situation with an imperfect test. I feel that whether you're right or wrong about that, "regression toward the mean" does mean "regression toward the population's mean" even in the test/retest situation.

 

I don't "feel" it's that way. It IS that way. That's the math. I don't feel you're wrong, you ARE wrong. Because the sh-- you're shoveling is NOT the math.

 

But given the fact that we are now (as far as I'm aware) in agreement about the underlying phenomenon and its effects, it would be stupid to spend another 50 pages arguing about a mere definition.

 

We're not even remotely close to agreement...because I haven't forgotten what started this circus: your wacky pseudo-Nazi idea that you can eugenically breed a master race. One of the objections was that regression toward the mean of intelligence through successive populations would mitigate the effect of any breeding program. As long as you persist in misunderstanding the basic math, you can whitewash any effect of regression away by claiming that a sufficiently accurate test will eliminate error and therefore nullify regression toward the mean. That is wrong mathematically - because error is not causing that effect. The statistical distribution of intelligence correlated across generations with a correlation factor of less than 1 is what causes it...which means it'll never work no matter how accurate your test is. (Never mind that correlating a test with a retest is completely different from correlating parental traits with child traits - a child's trait is not a retest of the parents' traits.) This was never about statistics; it was about you spewing Nazi bull sh-- as though it was credible science. So I attacked it on the basis of science.

[DC Tom]

Top 50 in what?

 

Small engine repair.

[Ramius]

Top 50 in what? Universities get ranked differently on their programs. When I graduated from the University of Illinois, my program was ranked top in the nation in research. FSU's Chem and Biochem programs are ranked within the top 25 of the country.

 

Thanks EC. Nice to have someone else mention it. Funny how he wont admit what college he went to. But McDonalds Hamburger U is probably ranked top 50 in hamburger schools. I should ask him what its like having grimace as a professor.

[EC-Bills]

Thanks EC. Nice to have someone else mention it. Funny how he wont admit what college he went to. But McDonalds Hamburger U is probably ranked top 50 in hamburger schools. I should ask him what its like having grimace as a professor.

 

You're welcome More importantly, we should ask was Grimace really Grimace before he met HA?

[DC Tom]

Thanks EC. Nice to have someone else mention it. Funny how he wont admit what college he went to. But McDonalds Hamburger U is probably ranked top 50 in hamburger schools. I should ask him what its like having grimace as a professor.

 

"I'm sorry my homework's late, Dr. Grimmace. The Hamburgler stole it..."

[DC Tom]

You're welcome More importantly, we should ask was Grimace really Grimace before he met HA?

 

Yes, he was.

 

But afterwards, he changed his name to Barney.

[EC-Bills]

"I'm sorry my homework's late, Dr. Grimmace. The Hamburgler stole it..."

 

[Orton's Arm]

Funny how he wont admit what college he went to.

If I did mention the college I went to, you and Bungee Jumper would be the first off the line to make jokes disparaging it. The college itself wouldn't matter--it could be the University of Michigan, Notre Dame, whatever. Just as the articles from Stanford, Duke, etc. didn't stop the two of you from making jokes about regression toward the mean, the school's actual pedigree wouldn't stop the two of you from denigrating it. And those foolish enough to listen to the two of you would falsely assume there was some truth to the jokes.

 

What harm are jokes on a message board? None, except that some of the people reading them--hey, maybe some of the people actually writing them--would be in a position to hire and fire others. If, say, GG learned that an applicant graduated from the same school as me, do I trust him to do the right thing and not hold that commonality against the applicant? Absolutely not. If I'm keeping my mouth shut about specifics, it's to protect my classmates from people just like you.

[Orton's Arm]

Uhhh...because you said error causes the population to regress toward the mean. Because you see, when you say something, and then deny you said it, the denial does not change the fact that you actually said it. It just makes you look stupid.

 

1) You acknowledged it today. After four MONTHS of denying it.

2) Your "Monte Carlo" simulation was not a Monte Carlo simulation. It was a numerical simulation...but not a Monte Carlo simulation. So please stop calling it that.

3) It was a piss-poor numerical simulation, because - again - you confused the distribution of individual error with the distribution of the population. THEY ARE TWO DIFFERENT THINGS, HENCE NOT THE SAME. I keep repeating that kindergarten-level phrase because you are incapable of grasping that kindergarten-level concept.

We absolutely do NOT agree. In a test-retest situation, the value of a measurement is established as (actual value) + (error term). In a test-retest situation, the actual value is CONSTANT, the error term is VARIABLE. Ergo, an individual measurement in a test-retest situation will only vary by the error term, which will regress toward the mean error for extreme values of error. Over a bulk population of measurements, the net error is ZERO, so it does NOT cause any regression toward the population mean. That is mathematical FACT. The reason you don't understand this concept is because you do not understand the kindergarten-level concept of THINGS THAT ARE DIFFERENT ARE NOT THE SAME.

 

The reason you mistakenly believe error is causing regression toward the population mean is because you establish a sample set of scores with a mean positive net error and discard those with mean negative net error. Your sample DOES NOT have normally distributed error. But then, when you retest, the error, being completely uncorrelated between tests, becomes normally distributed. BUT THIS IS ONLY THE BEHAVIOR OF THE ERROR TERM OF THE MEASUREMENT. When you choose your sample set of scores, you are effectively fixing the (actual value) term as a constant. Ergo, you've defined it as NOT REGRESSING TOWARD THE MEAN.

 

Your problem - again - is that you are completely incapable of distinguishing between the two distributions. A large part of the reason for this is that you're drawing on sources like Wikipedia and Hyperstats, using terms like "chance" and "luck", and failing to understand that these are not the same as error or variance. Again, you don't understand the math, so you can't see that THINGS THAT ARE DIFFERENT ARE NOT THE SAME THING.

 

No, you said way back in November: "I am measuring the regression of I.Q. scores. Someone who obtains a score that's far from the mean on the first test, more often than not, will get a score that's closer to the mean upon taking a second test." You specifically deny the existence of two different distributions, and claim measurement error of individual measurements and variance in a statistical distribution of measurements are identical.

I don't "feel" it's that way. It IS that way. That's the math. I don't feel you're wrong, you ARE wrong. Because the sh-- you're shoveling is NOT the math.

Such a long post, and yet with so very little comprehension of anything I've been writing for well over 50 pages. Let me give you an example with which you're now no doubt sickeningly familiar. (Ramius, the fact that I've given this example many times before means you don't get to accuse me of flip-flopping.)

 

Consider a population with 1000 people with true I.Q.s of 130, 100 with true I.Q.s of 140, and 10 with true I.Q.s of 150. They're given an I.Q. test in which there's a 20% chance of getting lucky and scoring 10 points too high, a 20% chance of getting unlucky and scoring 10 points too low, and a 60% chance of being scored correctly. Of the people who score a 140 on the test, 200 will be lucky 130s, 60 will be correctly scored 140s, and 2 will be unlucky 150s. When those who scored a 140 are retested, the lucky 130s will (on average) receive a 130, the correctly scored 140s will, on average, receive a 140, and the unlucky 150s will, on average, receive a 150. The pool of people who scored a 140 on the first test contains more lucky 130s than unlucky 150s. When that group is retested, its average score on the retest will be lower than 140--closer to the population's mean.

 

What on earth about the above paragraph could possibly justify you in thinking that I'm incapable of distinguishing between the distribution of the population and the distribution of the error term? Not only is the distinction itself absurdly easy to understand, I've repeatedly demonstrated ample grasp of it. I've always been very clear about the distinction between measured I.Q.s and true I.Q.s; and that the observed changes were strictly due to changes in the measurement error term, not the underlying I.Q.s for individual people. Other people aren't as dumb as you think! Get that through your head! You don't need to go around repeating "Things that are different aren't the same." The reason you don't need to go around repeating that is because other people actually have functioning brains.

 

I did not say that error causes the underlying population to regress toward the mean. For you to be so totally ignorant of my position after 50 pages of repeating it is simply inexcusable. The presence of measurement error is necessary for test scores to regress toward the population mean in a test/retest situation. If you had an error-free test, nobody would get lucky or unlucky when taking it. Everyone would be measured correctly the first time around, so their scores wouldn't change upon being retested. It's the dynamic of a) people being normally distributed, b) being given an error-prone test, c) being placed into a subset based on their test scores, and d) being retested which causes the movement of the test scores toward the population mean. The underlying values don't change, and I've never even hinted that they do. Dude, seriously. Have you seen me go around saying, "Joe was a true 130 who got unlucky when he took the test. In fact, he got so unlucky he became a true 120 and thereby regressed toward the population mean." I mean, seriously. If I'd been saying stuff like that, you'd be perfectly justified in your characterization of my views. As it is, you're arguing against a straw man. I don't know whether you've deliberately created the straw man, or whether you honestly didn't bother to take the time to understand my posts.

We're not even remotely close to agreement...because I haven't forgotten what started this circus: your wacky pseudo-Nazi idea that you can eugenically breed a master race. One of the objections was that regression toward the mean of intelligence through successive populations would mitigate the effect of any breeding program. As long as you persist in misunderstanding the basic math, you can whitewash any effect of regression away by claiming that a sufficiently accurate test will eliminate error and therefore nullify regression toward the mean. That is wrong mathematically - because error is not causing that effect. The statistical distribution of intelligence correlated across generations with a correlation factor of less than 1 is what causes it...which means it'll never work no matter how accurate your test is. (Never mind that correlating a test with a retest is completely different from correlating parental traits with child traits - a child's trait is not a retest of the parents' traits.) This was never about statistics; it was about you spewing Nazi bull sh-- as though it was credible science. So I attacked it on the basis of science.

The phrase "master race" is one you've introduced into the discussion, and is nothing more than cheap and easy propaganda on your part. And maybe you think your intellectual dishonesty is justified because you're fighting what you at least claim to believe is "Nazism." For my own part, I believe intellectual dishonesty is never justified, but that's just me.

 

My actual view is that the average stupid person has a lot more person than the average smart person; and that financial incentives should be used to encourage a somewhat saner reproductive outcome. If that's Nazism, then John Kerry is Karl Marx.

 

In an attempt to discredit my position, you pointed out that if two parents both get, say, a 140 on an I.Q. test, their children will, on average, have I.Q.s somewhere between 140 and the population's mean. My purpose in discussing the test/retest phenomenon was to demonstrate that the population of people who obtained test scores of 140 contains more lucky 130s than unlucky 150s. Therefore, while those parents may have had measured I.Q.s of 140, their true I.Q.s were lower. So at least some of what appears to be a case of children regressing toward the mean is actually just that their parents weren't as far away from the mean as their test scores indicated.

 

On the other hand, if you have two very tall parents, their children will generally also be tall; but not as tall as their parents. This regression toward the mean apparently holds true for just about every trait. On the surface, it would seem regression toward the mean would keep species from changing very much over the long term. Whether parents are the fastest or the slowest, the smallest or the biggest, the smartest or the dumbest, their children will generally be closer to the average than their parents. Nevertheless, both natural and artificial selection can produce powerful, long-term change. While regression toward the mean may slow the pace of change, it can't change the direction, nor can it dampen the ultimate magnitude of it. Darwinistic forces were strong enough to gradually change single-celled organisms into human beings, despite the fact that the dampening influence of regression toward the mean was presumably relevant every step of the way. To imagine that regression toward the mean has somehow locked our species into one particular long-term outcome for intelligence is just plain stupid.

[DC Tom]

Such a long post, and yet with so very little comprehension of anything I've been writing for well over 50 pages. Let me give you an example with which you're now no doubt sickeningly familiar. (Ramius, the fact that I've given this example many times before means you don't get to accuse me of flip-flopping.)

 

Consider a population with 1000 people with true I.Q.s of 130, 100 with true I.Q.s of 140, and 10 with true I.Q.s of 150. They're given an I.Q. test in which there's a 20% chance of getting lucky and scoring 10 points too high, a 20% chance of getting unlucky and scoring 10 points too low, and a 60% chance of being scored correctly. Of the people who score a 140 on the test, 200 will be lucky 130s, 60 will be correctly scored 140s, and 2 will be unlucky 150s. When those who scored a 140 are retested, the lucky 130s will (on average) receive a 130, the correctly scored 140s will, on average, receive a 140, and the unlucky 150s will, on average, receive a 150. The pool of people who scored a 140 on the first test contains more lucky 130s than unlucky 150s. When that group is retested, its average score on the retest will be lower than 140--closer to the population's mean.

 

What on earth about the above paragraph could possibly justify you in thinking that I'm incapable of distinguishing between the distribution of the population and the distribution of the error term? Not only is the distinction itself absurdly easy to understand, I've repeatedly demonstrated ample grasp of it. I've always been very clear about the distinction between measured I.Q.s and true I.Q.s; and that the observed changes were strictly due to changes in the measurement error term, not the underlying I.Q.s for individual people. Other people aren't as dumb as you think! Get that through your head! You don't need to go around repeating "Things that are different aren't the same." The reason you don't need to go around repeating that is because other people actually have functioning brains.

 

I did not say that error causes the underlying population to regress toward the mean. For you to be so totally ignorant of my position after 50 pages of repeating it is simply inexcusable. The presence of measurement error is necessary for test scores to regress toward the population mean in a test/retest situation. If you had an error-free test, nobody would get lucky or unlucky when taking it. Everyone would be measured correctly the first time around, so their scores wouldn't change upon being retested. It's the dynamic of a) people being normally distributed, b) being given an error-prone test, c) being placed into a subset based on their test scores, and d) being retested which causes the movement of the test scores toward the population mean. The underlying values don't change, and I've never even hinted that they do. Dude, seriously. Have you seen me go around saying, "Joe was a true 130 who got unlucky when he took the test. In fact, he got so unlucky he became a true 120 and thereby regressed toward the population mean." I mean, seriously. If I'd been saying stuff like that, you'd be perfectly justified in your characterization of my views. As it is, you're arguing against a straw man. I don't know whether you've deliberately created the straw man, or whether you honestly didn't bother to take the time to understand my posts.

 

The phrase "master race" is one you've introduced into the discussion, and is nothing more than cheap and easy propaganda on your part. And maybe you think your intellectual dishonesty is justified because you're fighting what you at least claim to believe is "Nazism." For my own part, I believe intellectual dishonesty is never justified, but that's just me.

 

My actual view is that the average stupid person has a lot more person than the average smart person; and that financial incentives should be used to encourage a somewhat saner reproductive outcome. If that's Nazism, then John Kerry is Karl Marx.

 

In an attempt to discredit my position, you pointed out that if two parents both get, say, a 140 on an I.Q. test, their children will, on average, have I.Q.s somewhere between 140 and the population's mean. My purpose in discussing the test/retest phenomenon was to demonstrate that the population of people who obtained test scores of 140 contains more lucky 130s than unlucky 150s. Therefore, while those parents may have had measured I.Q.s of 140, their true I.Q.s were lower. So at least some of what appears to be a case of children regressing toward the mean is actually just that their parents weren't as far away from the mean as their test scores indicated.

 

On the other hand, if you have two very tall parents, their children will generally also be tall; but not as tall as their parents. This regression toward the mean apparently holds true for just about every trait. On the surface, it would seem regression toward the mean would keep species from changing very much over the long term. Whether parents are the fastest or the slowest, the smallest or the biggest, the smartest or the dumbest, their children will generally be closer to the average than their parents. Nevertheless, both natural and artificial selection can produce powerful, long-term change. While regression toward the mean may slow the pace of change, it can't change the direction, nor can it dampen the ultimate magnitude of it. Darwinistic forces were strong enough to gradually change single-celled organisms into human beings, despite the fact that the dampening influence of regression toward the mean was presumably relevant every step of the way. To imagine that regression toward the mean has somehow locked our species into one particular long-term outcome for intelligence is just plain stupid.

 

 

I'm pretty sure there's nothing above worth reading. Same old nonsense. You're still clueless.

[EC-Bills]

If I did mention the college I went to, you and Bungee Jumper would be the first off the line to make jokes disparaging it. The college itself wouldn't matter--it could be the University of Michigan, Notre Dame, whatever. Just as the articles from Stanford, Duke, etc. didn't stop the two of you from making jokes about regression toward the mean, the school's actual pedigree wouldn't stop the two of you from denigrating it. And those foolish enough to listen to the two of you would falsely assume there was some truth to the jokes.

 

What harm are jokes on a message board? None, except that some of the people reading them--hey, maybe some of the people actually writing them--would be in a position to hire and fire others. If, say, GG learned that an applicant graduated from the same school as me, do I trust him to do the right thing and not hold that commonality against the applicant? Absolutely not. If I'm keeping my mouth shut about specifics, it's to protect my classmates from people just like you.

 

What a crock of sh*t!

[GG]

What harm are jokes on a message board? None, except that some of the people reading them--hey, maybe some of the people actually writing them--would be in a position to hire and fire others. If, say, GG learned that an applicant graduated from the same school as me, do I trust him to do the right thing and not hold that commonality against the applicant? Absolutely not. If I'm keeping my mouth shut about specifics, it's to protect my classmates from people just like you.

 

I can certify that I judge people strictly on their merit of laying cheese on the burger, not the diploma on the wall.

[EC-Bills]

I can certify that I judge people strictly on their merit of laying cheese on the burger, not the diploma on the wall.

 

That's not true, you passed me over because I graduated from Illinois and not Wisconsin!

[DC Tom]

I can certify that I judge people strictly on their merit of laying cheese on the burger, not the diploma on the wall.

 

Yeah...but the University of California system makes the best fryer operators...

[GG]

That's not true, you passed me over because I graduated from Illinois and not Wisconsin!

 

That's because Wisconsiners have an 80% cheesehead heritability factor.

[Alaska Darin]

With respect to Ramius?

Pretty much with respect to anything. Don't worry, I get the fact that you're lonely and this attention helps you get through the day.

 

"A Top 50 University" - that remind anyone else of BF's high school in the "Retatta thread"?

[DC Tom]

"A Top 50 University" - that remind anyone else of BF's high school in the "Retatta thread"?

 

True. Someone does have to be at the bottom of the class. Just because you graduate from a top 50 university, doesn't mean the university necessarily wants to be associated with you.

[Ramius]

Yeah...but the University of California system makes the best fryer operators...

 

The UT system grads are better suited for BK, where they only need to stack meat and cheese. Adding complicated ingredients like lettuce and tomatoes gets them all kinds of confused. Case in point: mike williams...has that guy EVER eaten a vegetable?

[Pine Barrens Mafia]

"A Top 50 University" - that remind anyone else of BF's high school in the "Retatta thread"?

 

Damn you, beat me to it.