Sat in a philosophy class today.

[Daldolma]

nope, i know relatively little about iq testing. i don't really understand how scores can vary so significantly if these test actually measure what they purport to measure. can general intelligence really fluctuate as you age?

anyway, i preferred that conversation to hbb defining implication in terms of gay blowjobs

[Ektar]

I can play that game too... you're wrong hbb.

it's a fucking verb and there are no boundaries on it. I can say things that are not true. just because person 1 thought it doesn't mean person 2 can't say it. it CAN happen.

[Barkingturtle]

Hey, I would like a frosty beer and a blowjob.

[FoxxHound]

Originally Posted by Alawen [You must be logged in to view images. Log in or Register.]

BMI 27.3. You're about 15 pounds overweight.

What about me? I am 5'7-5'8 and roughly 140.

[Alawen]

Originally Posted by Daldolma [You must be logged in to view images. Log in or Register.]

nope, i know relatively little about iq testing. i don't really understand how scores can vary so significantly if these test actually measure what they purport to measure. can general intelligence really fluctuate as you age?

anyway, i preferred that conversation to hbb defining implication in terms of gay blowjobs

I'm going to start with the very basics of psychometrics, so my apologies if this is review. I mentioned the elements of standardization, validity, and reliability in a previous post.

In brief, standardization is a given test being delivered in the same way given different physical locations, test administrators, and so on. If you've taken the SAT or the ACT, you've experienced their attempts to create a very controlled environment for taking the test.

Validity is the quality of testing what you are trying to test. This is what HBB is questioning--whether IQ is a valid test of intelligence. Validity is viewed from three perspectives: content, criterion, and construct. This is why the underlying theory of intelligence is important. I think Loraen is mostly objecting to the Cattell model of generalized intelligence; he would probably be more comfortable with Gardner's theory of multiple intelligences.

Reliability is the consistency between assessments and this is what you're questioning. It also has three subcategories, which are stability (also called test-retest), alternate form, and internal consistency. Obviously, stability is the characteristic you're calling into question.

You use a coefficient of variation to measure test-retest reliability (the quotient of standard of deviation and mean). Coefficients for both Standford-Binet and the Wechsler tests are around .90, and coefficients between the two tests, which have very different histories, are approximately .85. These are not results from a single study--this is a heavily researched area.

Most people have never taken a real IQ test. They may have received an estimated IQ based on a standardized achievement test, or taken some hokey short form internet test, but these approaches fail at all of the above. All of the standardized IQ tests require a skilled tester and quite a bit of time. As a result, they're expensive. As an aside, the popular Jung-based Myers-Briggs assessment fails horribly at reliability. Of the four elements, the only consistent measurement comes from the introvert/extrovert axis.

Returning to your question for explanations of the variance that does exist, it probably makes the most sense to consider Cattell's model. Up to this point, I've done very little speculation. This part is mostly my own thoughts. It seems unlikely that fluid reasoning (Gf) is subject to much variation. It doesn't seem to me that people learn things like curiosity and creativity. They seem to have them from a young age or not. However, it is the expressed purpose of a liberal arts education to teach logic, rhetoric, and critical analysis. Perhaps there is evidence of fluctuation in Gf between high school seniors and those same students graduating from a four-year liberal arts curriculum.

Within the limits of the model, then, variation in intelligence would most likely come from crystallized intelligence, Gc. It makes perfect sense that skills, knowledge, and experience could expand or contract with continued learning or disuse. Some of that will almost completely atrophy given a decade or two of neglect. On the other hand, some people are always learning. I like to think of myself in that group, though my skills in higher math are abominable now. I have to look up almost everything beyond simple trigonometry.

In brief, variance in test-retest reliability for standardized IQ tests is pretty acceptable, depending on what you're looking for. I think there's a lot of confusion from the simple fact that most people have never taken a real IQ test.

[Alawen]

Originally Posted by FoxxHound [You must be logged in to view images. Log in or Register.]

What about me? I am 5'7-5'8 and roughly 140.

At 5'8", your BMI is 21.3, right in the middle of normal weight. You're probably in pretty decent shape. The National Institute of Health has a BMI calculator at NIH BMI calculator.

[Kagatob]

This thread makes me not that sad that my new position won't be having general internet access.

[myriverse]

Originally Posted by Daldolma [You must be logged in to view images. Log in or Register.]

nope, i know relatively little about iq testing. i don't really understand how scores can vary so significantly if these test actually measure what they purport to measure. can general intelligence really fluctuate as you age?

They measure capacity to learn, not what is learned. Typically, there isn't much fluctuation in "capacity to learn" as you age after 6 or so years. However, your brain can be trained to learn more. Also, there can be a 20pt fluctuation just based on environmental factors: good diet, sleep, exercise, etc.

[Alawen]

Originally Posted by Kagatob [You must be logged in to view images. Log in or Register.]

This thread makes me not that sad that my new position won't be having general internet access.

We'll all miss your brilliant insights and bigotry.

[Alawen]

I just found an interesting study about this that was published last December in Neuron. It was an online test with tens of thousands of respondents, and they concluded that intelligence has three distinct elements: memory, reasoning, and verbal competence. The authors are challenging conventional IQ testing, which isn't new, but here's what I found noteworthy: "Intriguingly, people who regularly played computer games did perform significantly better in terms of both reasoning and short-term memory."