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IQ Tests

I think the best hypothesis is that g is working memory capacity plus speed of processing.

These are real things we can measure-- how fast neurons fire; how much info people can hold in consciousness and act on.

These are basic cognitive processes that are highly plausible as an explanation / definition of what g is.
 
Dat ain't no strawman...

Sure it is. I can tell you what gravity is, without simple handwaving to "explanatory capacity."

Gravity is a force. It behaves like other forces we know about. I can build a general purpose "force detector" (I believe the technical term is dynometer or dynamometer, and you can get them out of
catalogs) that will detect, among other things, gravity. I can show that the dynometer responds to other kinds of forces and calibrate it so that I know it works as a "force detector."

If you want an ultimate explanation about how gravity works, the physicists are still working on that. Science isn't typically in the habit of providing "ultimate explanations" about anything, and the detailed workings of gravity are still a mystery.

But you can't even tell me what 'g' is, let alone build a detector for it. Except by building an IQ test, and then telling me that "We can tell 'g' is real, because IQ tests detect it. And we can tell IQ tests work, because they detect 'g'."

Physicists have this problem all the time, for example, in the detection of gravitons. We can't calibrate a graviton detector unless we know that gravitons exist -- and we can't be sure that gravitons exist until we can detect them. Unlike psychologists, reputable physicists don't claim to be certain that gravitons actually exist precisely because they are aware of this calibration problem.

Jensen, however, apparently isn't.
 
I think the best hypothesis is that g is working memory capacity plus speed of processing.

These are real things we can measure-- how fast neurons fire; how much info people can hold in consciousness and act on.

My understanding is that "how fast neurons fire" has been tested and found to be uncorrelated with IQ. Have I missed some papers?

As to "how much info people can hold in consciousness" -- how do you express that hypothesis in a testable fashion that doesn't come back to "well, it correlates with scores on an IQ test"?
 
I think the best hypothesis is that g is working memory capacity plus speed of processing.

These are real things we can measure-- how fast neurons fire; how much info people can hold in consciousness and act on.

These are basic cognitive processes that are highly plausible as an explanation / definition of what g is.

Sounds pretty simplistic to me.

Do you really think that neuron firing speed and memory "capacity" account for differences in intelligence?

How is memory capacity to be measured?

What makes you think that memory capacity has anything to with what can be held in consciousness (whatever that means)?

What about differences in patterns of memory access?
What about differences in forgetting?
Is the speed of neuron firing a significant factor in processing speed?
Which processing speed? What makes you think there is only one?
What about differences in how processing is performed?

There are many many more questions. Why aren't you asking them?

You've got a lot of nerve speculating that "g is working memory capacity plus speed of processing".
 
Nice pun with the nerve reference!

I really do think this, so do lots of other people who actually publish in the field.

Even located "where in the brain" working memory is:

http://www.rashmisinha.com/archives/04_06/working-memory-hci.html

WM has a precise meaning in cognitive psychology-- it's what we used to call short term memory. It's literally the place where thought is accomplished.

The older short term memory idea emphasized only storage of info (like looking up a phone number, keeping it in STM til you dial, then forgetting it).

WM emphasizes both storage and processing (perhaps the best example being balancing your checkbook in your head. In fact, I have a publication that looks at mental squaring-- squaring 2 digit numbers in one's head-- has a method of examining working memory efficiency.

People who have high g also do very well on WM span tasks-- the ability to hold info in consciousness, be distracted, yet still retain the info, is key to what g is.

I mention speed of processing because it is intertwined with WM capacity. How fast we process information determines how much info we can process at one time and vice versa.

The research on the importance of WM as a cogntive construct; what happens to WM as one ages, and how WM relates to psychometric g is impressive.

I guess WM's probably an artifact too!

At any rate, I'm not up on the year 2000 and beyond literature, but I know there's lots of research showing scores on a paper and pencil g loaded IQ test predict the speed with which neurons in one's brain fire, and even predict individual differences in myelenization (sp-- the fatty gook on neurons that makes em fire faster or more efficiently).

Just one example of a research strategy showing the realness of g and it's relation to either speed or working memory:

Give a g loaded IQ test to a bunch of 20 year olds and a bunch of 70 year olds. You will see huge differences on the more fluid like measures of g.

Also measure WM with a span task.

Regress the span task in with the age difference in g, and the age difference goes away.

Regress in anything else (personality, motivational factors, or the disuse hypothesis) and the age difference remains.

I don't know why people find this so offensive. The evidence for this kind of stuff is overwhelming, and readilly available for anyone skeptical to verify.
 
Recent research has begun to explore what seem to be still more direct measures of neural processing. Reed and Jensen (1992) have used visual evoked potential (VEP) techniques to assess what they call "nerve conduction velocity" (NCV). To estimate this velocity, each subject's head length (a rough index of the distance between the eye and the occipital cortex) is divided by the mean latency of an early component (N70 or P100) in his or her VEP pattern. In a study with 147 college-student subjects, this measure correlated r =.26 with scores on an unspeeded test of intelligence. (A statistical correction for the restricted subject range raised the correlation to r = .37.) Other researchers have also reported correlations between VEP parameters and intelligence test scores (Caryl, 1994). Interestingly, however, the same "conduction velocities" were not correlated with the same subjects' choice reaction times (Reed & Jensen, 1993). Other researchers have also reported correlations between VEP parameters and intelligence test scores (Caryl, 1994).

This is old stuff, but the best I can do right now. I'd bet this whole argument there's a string of recent studies showing strong r's with speed and WM and g.

I did see that Eysenck-- another real big name in the field-- reports correlations as high as .8 between g and neural speed.
 
LOL. Guys who are sure their (non-existent) g is way up on the high end arguing about a factor that cannot be studied due to the politically and socially unpalatable results that come up when it is being studied. :p
 
From Jensen (btw, even if he's wrong about everything, I think you woefully underestimate him as a scientist).

Damn Mendel reifying his artifactual gene thingy:

Mendel, in 1865, explained the results of his simple
breeding experiments with peas in terms of 'factors' (the word gene
hadn't yet come into existence), about which nothing was known, except
that they served in Mendel's model as the cause of the observed
hereditary variation in a few specific characteristics of peas.

5. During the subsequent 88 years, Mendel's nondescript construct was
elaborated both theoretically and empirically. T. H. Morgan
hypothesized that genes are arranged on the chromosomes and, on the
basis of linkage analyses from breeding experiments with fruit flies,
measured genes' relative positions on the chromosome. (His ordinal
scale [in 'decimorgans' or 'centimorgans'] at the time would probably
have been unacceptable to Barrett.) Then H. Muller found that specific
functions of single genes could be knocked out or mutated by X-rays,
thereby further establishing their identity as molecular entities.
Finally, in 1953, Crick and Watson discovered the specific molecular
structure of the genetic code. (All of these scientists except Mendel
won the Nobel Prize for their contributions.) This chain of development
scarcely resembles Barrett's requirement that scientists must already
know the essence of what they are investigating and measuring before
they begin their empirical research.
 
Mendel, in 1865, explained the results of his simple
breeding experiments with peas in terms of 'factors' (the word gene
hadn't yet come into existence), about which nothing was known, except
that they served in Mendel's model as the cause of the observed
hereditary variation in a few specific characteristics of peas.

5. During the subsequent 88 years, Mendel's nondescript construct was
elaborated both theoretically and empirically.


T. H. Morgan
hypothesized that genes are arranged on the chromosomes and, on the
basis of linkage analyses from breeding experiments with fruit flies,
measured genes' relative positions on the chromosome. (His ordinal
scale [in 'decimorgans' or 'centimorgans'] at the time would probably
have been unacceptable to Barrett.) Then H. Muller found that specific
functions of single genes could be knocked out or mutated by X-rays,
thereby further establishing their identity as molecular entities.


Cool. Thank you for so eloquently proving my point.

The genetics researchers recognized that Mendel's "factors," while a convenient enough model, weren't necessarily real and did a lot of work to establish what they actually were.

Someone came up with a testable hypothesis (they're molecular strucures arranged on the chromosomes), and someone else managed to find physical evidence proving the existence of such structures.

What's the difference between this and 'g'? Night and day. Jensen and his incompetent ilk apparently assume that because Mendel's genetic "factors" were real, so must their cognitive ones. There's no empirical work to confirm the existence, no substantial theory about where 'g' arises, and no physical evidence whatsoever.
 
If by training them you actually learn how to calculate faster and more accurately, or you enhance your vocabulary, then yes, you probably enhance those facettes of your intelligence that are part of what is also called "crystalline intelligence". On the other hand - "fluid intelligence" (e.g. problem solving) is a lot harder to train. But in any case, it mostly means that you learn from the tasks and get better at them. This effect is extremely strong if you do the same test more than once, it may exist when doing different tests with similar tasks, and it will probably not exist at all if presented with completely unknown tasks. This only shows that there are other influences on a test-result than just your intelligence. Most if not all psychological concepts can not be measured with absolute precision. That does not mean they are not existing, just that the measurement is not perfect. It's always an estimation of the real value. Comparing a measured IQ of 120 with one of 121 and saying one was higher than the other is absurd. Comparing a result of 100 with one of 130 is justified. The critical difference is a property of the test used, and is a function of its statistical reliability.

I did manage, through repeated study and test-taking, to get a score of 178 on a mostly problem-solving test. I've noticed that, during this process (it took a few years, on and off) my general ability to analyse situations and solve problems did significantly improve.

So to me, that it can be studied, improved upon, and allowed to atrophy (I don't think I'd be able to get a 178 now) is a given.
 
Cool. Thank you for so eloquently proving my point.

The genetics researchers recognized that Mendel's "factors," while a convenient enough model, weren't necessarily real and did a lot of work to establish what they actually were.

Someone came up with a testable hypothesis (they're molecular strucures arranged on the chromosomes), and someone else managed to find physical evidence proving the existence of such structures.

What's the difference between this and 'g'? Night and day. Jensen and his incompetent ilk apparently assume that because Mendel's genetic "factors" were real, so must their cognitive ones. There's no empirical work to confirm the existence, no substantial theory about where 'g' arises, and no physical evidence whatsoever.

Testable hypothesis with g have been made, and born fruit, as bpesta explained earlier in this thread in a post which you seem to have ignored entirely. Either show that the correllation is not present or admit that you are wrong.
 
Testable hypothesis with g have been made, and born fruit, as bpesta explained earlier in this thread in a post which you seem to have ignored entirely. Either show that the correllation is not present or admit that you are wrong.

Forget it - he ignores everything that does not support his position. Name calling obviously being the last measure. I guess it might be because he does not know what a construct is. Proof for the existence of "g" for him would probably be when there's a region in the brain found that has "g inside" written over it.
In the meantime he doesn't even try to explain why people who are better at calculating tasks also tend do be better at other, seemengly unrelated tasks.
 
I did manage, through repeated study and test-taking, to get a score of 178 on a mostly problem-solving test. I've noticed that, during this process (it took a few years, on and off) my general ability to analyse situations and solve problems did significantly improve.

So to me, that it can be studied, improved upon, and allowed to atrophy (I don't think I'd be able to get a 178 now) is a given.

Did you take the same test over and over again, or were they different tests?
 
Meanwhile, could you explain how you demonstrate event A "causes" B without employing correlation?
 
Meanwhile, could you explain how you demonstrate event A "causes" B without employing correlation?
If you "employ" causation, you effectively "employ" correlation. It's self-evident that if A causes B, then A correlates with B. When trying to discover a causal relationship, you look for a correlation between A and B after controlling for C through Z.
 
If you "employ" causation, you effectively "employ" correlation.

RIght. But when you "employ" correlation, you don't necessarily "employ" causation.

Everyone in psychology -- except, evidently, IQ theologians -- recognizes that proof of correlation is not proof of causation.

Re-read Xeriar's post:

Either show that the correllation is not present or admit that you are wrong.

Evidently there are only two choices. According to Xeriar, either the correlation is absent -- or the correlation is present, and therefore so is the causation that Xeriar wants to infer but can't find a shred of evidence for. I deny both choices.

"Either show that bread does not rise, or admit that you were wrong and that fairies do cause bread to rise."

That's a classic example of a false dichotomy.

To make myself absolutely clear. I do not deny the correlation. I deny, emphatically, that the theories proposed to explain the correlations have any more basis in reality than do the theories that fairies are what causes bread to rise.

You can't prove that fairies exist by pointing at rising bread. You can't prove that g exists by pointing at inter-test correlation.
 
But you are just dancing around the inevitable; given a high positive correlation are you looking at cause/effect or other variables in the mix that effect both. If A>C,and A>B, and you observe B & C with high correlation, what now?

And in the case of IQ tests, what variables do you select to explain "reasonable" correlations of test scores to success in specific endeavors? Do you suggest IQ test results are all meaningless?
 

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