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  1. #1

    Default Bull Sh*t Codified

    I love statistics, and its applications. In particular to things like pattern recognition, classifiaction, computer vision and learning.

    Hower, the following technique is a quintessential example of the saying, "There are lies, damn, lies, and statistics".

    Factor analysis - Wikipedia, the free encyclopedia

    Read the disadvantages sections and you'll see why this technique is hoplessly unsatisfatory for studying something as complex as human beings.

    It has been said by many that the fundamental problem with psychological testing is that test makers have to use prejudice in making their questions and assigning interpretations to their answers. No amount of statistical manipulation is going to correct this.

    There is no such thing as "being unbiased" in any field of study. Even assuming a Gaussian distribution can be a horrible bias (as physicists know quite well). Weibull, Poisson, and Unform distributions are also quite common. Bimodal distributions (very different from "binomial" distributions) are also quite common. A nuanced understanding of the "Central Limit Theorem" will tell you that the natural place for assuming Gaussians are for sums and averages of independent random variables.

    To illustrate the utility of bias, consider a simple situation of measure defect rates of a products from a manfaturing facility. Very good facilities may show no defects for as long as we have time for publication of defect rates. No rational thinking human being with an ounce of common sense will publish a defect rate of "zero" even though "that is what the data shows". The common procedure is to assume (absolutley necessary) a Weibull distribution with a positive defect rate (and other fitting parameters based on prior "bias") and to keep adjusting the the parameters based on our "zero" defect rate for as many products has come up. This is just one example of a "corner case" where a bias is absolutely necessary to make inferrences that are meaningful. The more complex a system, the more corner cases that will come up.

    There is something fundamentally wrong about correlatory studies of systems as complex as parts of human beings. Let alone the more mysterious study of "mind" or "health" (let alone "mental health").

    First a reminder. Correlation does not imply a cause-effect relationship. I repeat, correlation does not imply a cause-effect relationship.

    However, the fundamental problem is that we inherently ignore what is unique about our system in correlatory studies, but it is the uniquness itself that is vital for system function. This is true even for systems much simpler that human beings.

  2. #2
    The elder Holmes Mycroft's Avatar
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    Quote Originally Posted by ygolo View Post
    Read the disadvantages sections and you'll see why this technique is hoplessly unsatisfatory for studying something as complex as human beings.
    .
    Well. That certainly hasn't been my experience of our species.
    Dost thou love Life? Then do not squander Time; for that's the Stuff Life is made of.

    -- Benjamin Franklin, Poor Richard's Almanack, June 1746 --

  3. #3

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    Quote Originally Posted by Mycroft View Post
    Well. That certainly hasn't been my experience of our species.
    Well I suppose I have a lower threshold for complexity. I think it is near imposible to create a theory that yeilds reliable and testable predictions about an individual.

    We are poor at predicting when someone is about to become a serial killer, and if the FBI profilers that came on during the Norhtern Virgina shootings are any indication, the speculation of your average Joe was as good.

    Similarily, I think we are horrible at predicting the who are best and brightest are also. Poincare, Feynman, and Crick are among history's greatest achievers of intellectual work, but their IQs paled in comparison to the world's highest IQ holder (an ENTP I believe), who writes advice columns (not a bad thing, but as far as "intellectual" achievement goes?).

    We can certainly find averages, corelations, and tendencies, but for the most part, I don't think they tell us much more than what our guts already do.

    There are some notable recent exceptions in behavioural finace and behavioral economics (A redrawing of the boundaries of the social "sciences" for the better I think. They are starting to ask better questions).

    Quite frankly, without some better gueses, no amount of data/psychometrics/statistical manipulation is going to significantly improve out understanding. Certainly not the self-reinforcing world views created by factor analysis or MBTI.

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    The elder Holmes Mycroft's Avatar
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    Your post prompted me to do a search. I'm quite taken aback by the number of people claiming to have IQs in the excess of 200.
    Dost thou love Life? Then do not squander Time; for that's the Stuff Life is made of.

    -- Benjamin Franklin, Poor Richard's Almanack, June 1746 --

  5. #5
    Senior Member ptgatsby's Avatar
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    Quote Originally Posted by ygolo View Post
    Well I suppose I have a lower threshold for complexity. I think it is near imposible to create a theory that yeilds reliable and testable predictions about an individual.
    How about groups of people?

    Quote Originally Posted by Mycroft View Post
    Your post prompted me to do a search. I'm quite taken aback by the number of people claiming to have IQs in the excess of 200.
    Online IQ tests are the bane of my existance. I'm very curious about IQ and intelligence in general... but you just can't have a real conversation about it outside of some very narrow fields.

    It doesn't help that a real IQ test will run you a couple of hundred bucks at least (the KAIT and the WAIS here were 400-500 and 300-600, estimated by one of the psychologists that referred me).

  6. #6

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    Quote Originally Posted by Mycroft View Post
    Your post prompted me to do a search. I'm quite taken aback by the number of people claiming to have IQs in the excess of 200.
    Can you expand on that? How many people did you find? and where?

    Quote Originally Posted by ptgatsby View Post
    How about groups of people?
    Large enough groups measuring simple enough traits, yes. Sometimes it may be useful to measure how much demand there will be for a product, and making decisions like that.

    But as far as understanding the human condition, I don't think it will tell us too much more than the trends and patterns we already see withough these approaches.

    Psychometrics on "intelligence", "personality", and other complex things like that, I find futile. I think we will miss too many "corner cases" taking statistical apporaches.

    To see how real science is done on complex systems, look at modern biology. The discovery of DNA, its structure, what genes actually express, etc.

    For a slightly older version, you could also look at the development of chemistry (for the more macrascopic ideal gas laws, to the periodic table, to P-chem (quantum mechanical modeling, and approximations based on them) , statistical mechanics implying thermodynamics, etc.)

    Certainly probability and statistics were important in the development of these scinces, but they hadn't become crutches to try and get the status of being "scientific". There was a pursuit of truth by whatever means made most sense. Plain and simple.

  7. #7
    Senior Member darlets's Avatar
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    Quote Originally Posted by Mycroft View Post
    Your post prompted me to do a search. I'm quite taken aback by the number of people claiming to have IQs in the excess of 200.
    I find it odd too. I could be wrong, but I thought I.Q results had a mean of 100 and a Standard deviation of 15.

    An I.Q of 190 is 6 S.D away from the mean. That's a really, really small % (99.99999980268% from Standard deviation - Wikipedia, the free encyclopedia )
    I think you're getting to the one in a billion level.
    "The time you enjoy wasting is not wasted time."
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    Quote Originally Posted by ygolo View Post
    Can you expand on that? How many people did you find? and where?
    I just ran a search for "world's highest IQ" on Google.
    Dost thou love Life? Then do not squander Time; for that's the Stuff Life is made of.

    -- Benjamin Franklin, Poor Richard's Almanack, June 1746 --

  9. #9
    Senior Member ptgatsby's Avatar
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    Quote Originally Posted by darlets View Post
    I find it odd too. I could be wrong, but I thought I.Q results had a mean of 100 and a Standard deviation of 15.

    An I.Q of 190 is 6 S.D away from the mean. That's a really, really small % (99.99999980268% from Standard deviation - Wikipedia, the free encyclopedia )
    I think you're getting to the one in a billion level.
    One thing to note is that the ability to measure IQ decreases above 150... quite dramatically... so the upper threshold of most IQ systems, which is still fuzzy, is about 160-170.

  10. #10
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    Quote Originally Posted by ptgatsby View Post
    One thing to note is that the ability to measure IQ decreases above 150... quite dramatically... so the upper threshold of most IQ systems, which is still fuzzy, is about 160-170.
    Makes sense. At that point nobody's smart enough to make questions for people that smart!
    Dost thou love Life? Then do not squander Time; for that's the Stuff Life is made of.

    -- Benjamin Franklin, Poor Richard's Almanack, June 1746 --

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