Are Republicans smarter than Democrats, conservatives dumber than liberals?

There was a big uproar over a fake study once where someone claimed red states had lower average IQs than blue states did. I thought this was stupid -- a well-designed study (even a fake one) would look at individuals and their party preferences, not whole states. I've noticed The Inductivist does a lot of work with the General Social Survey, so I followed his lead.

After doing so, I found that Half Sigma once did something similar. He kept his results to party ID, where mine also include political ideology. He also looked at trends (concluding Democrats are getting smarter relative to Republicans), where I just used the current data.

The GSS does two measures of IQ, vocab and reasoning. It also asks for party preference. Running a simple correlation matrix, I found that the number of words someone got right on a vocab test correlated with their proximity to the Republican side of the spectrum (.111). The reasoning test is broken down into individual questions, and most aren't significantly linked to party, but the ones that are point the same way. Republicans are smarter.

The weird thing is that when I replace political party with political ideology (conservative/liberal), I get the opposite result, though weaker. There's a -.029 correlation with vocabulary. (None of the reasoning tests gives a significant result.)

Why the different results? The first stereotype to come to mind is Southern Democrats who have low IQs and consider themselves conservative. And the Republican/conservative, Democrat/liberal link isn't as strong as you'd think for most Americans -- there's only a .310 correlation.

It's all quite disconcerting, because I consider myself much more conservative than Republican.

Gladwell retracts

Steve Sailer has the scoop on the first error I pointed out in this post. No word on the others, though those are more mischaracterizations than errors.

MSN stops posting episodes of Arrested Development online

They were adding three episodes every three weeks until the whole series was up ... then they stopped with half of Season 3 left, with no warning or explanation I've been able to find. Why?

I was really getting into the show, and I loved being able to watch it whenever I wanted without paying for DVDs. It seemed like they were selling ads well, too, so I don't get it. Unless they're trying to move copies of Season 3 -- the price is down to $14.99 on Amazon, which I'd find tempting if it weren't for the network promising and then not delivering.

I am such a nerd

I saw a reference to "the birthday problem" today (if you have n people in a room, what are the odds that at least two of them have the same birthday?), and the Wikipedia page didn't make much sense to me, so I worked at it until I solved it on my own. My answer is formulated differently than Wiki's, but setting it equal to .5, I get the right answer -- if you have 23 or more people in the same room, odds are at least 50-50 that two will have the same birthday. If you have 22 or fewer, the odds are that they all have different birthdays.

Since I wasted a lot of time, I figured I'd share my reasoning. Here's my solution:

1 - [( 364 / 365 ) ^ (( n ( n - 1 )) / 2 )]

Here's my method, as well as I can explain it. Whenever you're trying to figure out the odds of a group of people matching once or more, it's easier to find the odds of no one matching and subtract it from 1. With any two people, the odds of them not matching is 364/365.

So (1 - 364/365) is the answer when there are only two people in the room. When there are three people in the room, there are three possible matches -- AB, AC and BC -- so then the answer is 1- [(364 / 365) ^ 3]. Four people, six matches (AB AC AD BC BD CD), 1 - [(364 / 365) ^ 6]. For each new match, you have to multiply by 364/365 again, because each match reduces the odds that no one's shared a birthday yet.

When counting up the total matches, think of it as matching the first person in the room with everyone else, then matching the second person with everyone except the first person, with whom he's already been matched, and so on. Look back at the combinations for four people -- A is matched to B, C and D; then B still has to match with C and D; then C has to be matched with D. Our answer will be 1 - [(364/365) ^ total matches]

The biggest problem is converting the exponent into a formula. I looked at it like this: Using the matching idea, you multiply by 364/365 (n - 1) times (the first person in a group of four needs to be matched with three people), and then (n - 2) times, and so on, until (n - whatever) reaches 1. This looks like (364 / 365) ^ (n - 1) * (364 / 365) ^ (n - 2), etc.

When you're multiplying the same number with different exponents, you add the exponents. For example, (2 ^ 3) * (2 ^ 4) = 2 ^ 7. So to find the exponent, we have to summarize (n - 1) + (n - 2) + (n - 3) ...

The first question is how many "n"s we'll have once we've added all the terms. When n = 2, there's only 1, in (n - 1). (In this case, n - 2 = 0, so there's no point in adding 0.) And when n = 3, there are two "n"s, (n - 1) + (n - 2). In the formula, there is always one fewer "n"s than n's value. From this we get n(n - 1).

What I found most difficult was figuring out how to make the subtracted numbers add up. When n = 2, we subtract 1. When n = 3, we subtract 3 -- (n - 1) + (n - 2). Here's the table:

n   Subtracted number
2   1
3   3
4   6
5   10
6   15

Basically, you start out subtracting 1, and then you always subtract 1 more than you did last time. Formula-wise, and annoyingly enough, this is a repeat of the previous problem, (n - 1) + (n - 2), etc. I didn't really know where to go from here, so I decided to take a closer look at the way I starting solving the problem last time -- with the "n"s. Recall that answer was n(n - 1). I figured that this formula must be adjusted in some way to calculate the subtracted number based on n, so I wrote it out:

n   n(n - 1)
2   2
3   6
4   12
5   20
6   30

Not sure how you'd discover this algebraically, but visually it's easy to see that n(n - 1) / 2 equals the subtracted number in the exponent. And of course, this is subtracted from n(n - 1), and any number minus half of itself equals half of itself. So the exponent is n(n - 1) / 2.

To set the formula equal to .5, multiply it out and use logarithms (just type, for example, "log .5" in a Google search) and the quadratic formula .

Journalists are so awesome with statistics, part two

From The New York Times:

When Mr. Nutter takes office on Jan. 7, he will face a crime wave that has left at least 355 people dead so far this year and that gave Philadelphia the highest homicide rate of any big city in the country last year, with 406 killings — more per capita than even New York City, which has six times the population.

The whole point of a "per capita" (or "per person") statistic is that it doesn't matter what the population is. If a town of 10 people has one homicide and a town of 100 has 10, each has .1 homicides per capita. It's the same principle as the homicide rate, except that's usually calculated per 100,000 people -- consequently, since the writer already said Philadelphia has the highest homicide rate, it's redundant to say it has more murders per capita than New York does.

At first I thought the reporter meant to say that Philadelphia has a higher absolute number of homicides than the Big Apple, even though it has one-sixth the population. That would mean its per-capita homicide count is more than six times New York's. But that's not true -- a few weeks ago, NY already had 433. It's amazing that two big cities could be so close in count when they're so far apart in population, so the NYT's point stands, but it's obvious a math major didn't write that sentence.

Finally, Giuliani's crime cleanup left New York incredibly safe for a big city, so some context would be nice. If I were to rewrite the sentence, I'd either leave out New York altogether, or put a period after "406 killings" and add: "New York City, often considered a model of successful crime control, has a homicide rate about one-sixth of Philadelphia's."

Dawkins, right and wrong

Dave Weigel points to this part of a story:

Prof Dawkins, who has frequently spoken out against creationism and religious fundamentalism, replied: "I'm not one of those who wants to stop Christian traditions.

"This is historically a Christian country. I'm a cultural Christian in the same way many of my friends call themselves cultural Jews or cultural Muslims.

"So, yes, I like singing carols along with everybody else. I'm not one of those who wants to purge our society of our Christian history.

"If there's any threat these sorts of things, I think you will find it comes from rival religions and not from atheists."

Dawkin's personal view is mine exactly. But I think the very last line couldn't be more wrong: Many challenges to public religious displays come from atheists. American Atheists publicly takes a hard line on church-state separation, and a state director of theirs sued over a Christian display. A similar thing happened in my hometown. The opposition to "Under God" in the pledge came from an atheist.

It's true that rival religions and liberal bureaucrats (some of the latter even Christians themselves) join in, but to claim there's no organized atheist attempt to undermine Christian culture is absurd.

Ewww

Is this really such a promising fact?

Fast food makes such a savory scapegoat for our perpetual girth control failures that it's easy to forget we eat less than 20 percent of our meals at the Golden Arches and its ilk.

I don't mind the occasional fast food dinner when I have to go straight from work to some event or whatever, and I do that more than I should, but on average, close to 1 in 5 meals comes from a fast-food restaurant?

Even if eat-out-for-every-meal people are skewing the average, it seems high, and in 1995 the number was only 9 percent (another 5 percent of meals came from non-fast-food restaurants).

Awesome idea

Some college really should try this:

Harvard would simply collect (for the sake of argument) 1% of the student's income for the thirty years after graduation. Those going to hedge funds and law firms will pay more while those pursuing teaching or public interest work will pay less over time. ... it would place the burden of paying for higher education on the person who benefits most directly from the education: the student, rather than the parents.

Another benefit is that schools would spend less money on fields that are neither charitable (education, public service) nor profitable (banking).

Hoo boy

Steve Sailer has a veritable flood of information about a new academic paper.

From the press release :

"Human races are evolving away from each other," Harpending says. "Genes are evolving fast in Europe, Asia and Africa, but almost all of these are unique to their continent of origin. We are getting less alike, not merging into a single, mixed humanity." He says that is happening because humans dispersed from Africa to other regions 40,000 years ago, "and there has not been much flow of genes between the regions since then."

I'll be reading the paper and posting thoughts if I have them. Sailer's work is enough to keep anyone busy for awhile, though.

This does, of course, lend plausibility to the thesis that human populations differ significantly in the prevalence of important genes, including genes that influence IQ.

Malcolm Gladwell on IQ

The piece is just rife with inaccuracies:

[I]n 1994 Richard Herrnstein and Charles Murray, in "The Bell Curve," notoriously proposed that Americans with the lowest I.Q.s be sequestered in a "high-tech" version of an Indian reservation, "while the rest of America tries to go about its business."

No. No they did not propose this. They feared it, because in older times, even very smart people ended up working on family farms and in factories -- nowadays, we're more IQ-segregated than ever, and if this continues, we'll have a world where the bright and dull interact even less than they already do. They proposed a return to a world where neighborhoods, rather than governments, provided services, so people with lower IQs could find places in each community. See a more accurate quote/paraphrase job here.

Then this:

To the I.Q. fundamentalist, two things are beyond dispute: first, that I.Q. tests measure some hard and identifiable trait that predicts the quality of our thinking; and, second, that this trait is stable—that is, it is determined by our genes and largely impervious to environmental influences.

Wrong again. IQ fundamentalists, to the degree they exist, think IQ is stable over a person's lifetime, after age 5 or so, not that it is "impervious to environmental influences." It is simply a fact that environment influences IQ, and even the most hardcore IQ-philes know this. You'd have to ignore gigantic bits of evidence to claim otherwise.

And then:

From the perspective of an I.Q. fundamentalist, the fact that Africans score lower than Europeans on I.Q. tests suggests an ineradicable cognitive disability.

Nope. No one who knows what he's talking about automatically assumes that every IQ difference is genetic. There are a variety of ways to test where exactly the gap comes from, and both sides have some evidence.

For example, once could posit that the black-white income gap creates the black-white IQ gap -- but when you look at the data, whites and blacks with incomes of (say) $45,000 will still differ in their average IQs. Newer research looks at specific genes related to cognition and has found at least some of them to be unequally distributed through humanity. Some no-genetic-component arguments here. I'm an agnostic on the question, but this is an incredibly dishonest way to put the genetic-component side's view.

Next:

Drawing heavily on the work of J. Philippe Rushton—a psychologist who specializes in comparing the circumference of what he calls the Negroid brain with the length of the Negroid penis—Saletan took the fundamentalist position to its logical conclusion.

He's studied that, and it is a bit absurd. But it's just as absurd to say he "specializes" in this very specific question. His specialty, I'd say, is racial IQ differences in general.

The one positive thing I can say about this article is that it provides a decent summary of James Flynn's work.

Ballot-box shopping

This American Prospect article takes a pretty liberal definition of the word "disenfranchisement." It decries efforts to dictate to college students where they'll be voting, not whether. This issue has affected me -- for four years I went to school in Illinois but lived in Wisconsin over the summers, so I could pick which state to vote in.

The problem the article doesn't address: I personally witnessed explicit, organized attempts to get students from swing states to vote in their home elections. The current system actually gives students extra power. A law mandating that students vote at home or at college would solve this, and college towns' attempts to discourage student voting have the same effect.

However, there's no fair way to decide which way to force the issue. Many students go to an out-of-state school, but then return home, so they have an honest reason to vote in their home elections. But if you force everyone to do this, college students get no say in the communities they spend nine months of the year in.

It's an interesting issue worth taking sides on, but the story could have used a lot more nuance.

Nurture scores a hit

The New York Times has a terrific opinion piece making the case that racial IQ differences are completely environmental.

Most compelling argument:

[An] adoption study ... one not discussed by the hereditarians ... looked at black and mixed-race children adopted by middle-class families, either black or white, and found no difference in I.Q. between the black and mixed-race children. Most telling is Dr. Moore's finding that children adopted by white families had I.Q.'s 13 points higher than those of children adopted by black families. The environments that even middle-class black children grow up in are not as favorable for the development of I.Q. as those of middle-class whites.

...Joseph Fagan of Case Western Reserve University and Cynthia Holland of Cuyahoga Community College tested blacks and whites on their knowledge of, and their ability to learn and reason with, words and concepts. The whites had substantially more knowledge of the various words and concepts, but when participants were tested on their ability to learn new words, either from dictionary definitions or by learning their meaning in context, the blacks did just as well as the whites.

At the very least, this proves that environment can hugely influence the gap (which, of course, no one really disputes). If there is a genetic component, this would indicate it's a small one.

As I've mentioned before, though, this method of analysis is quickly becoming obsolete. It's simply not that effective to control for this, that and the other thing when instead you can look at specific genes, what they do and how they vary by race. This research is underway and will be reasonably thorough in 10 to 15 years. The writer sidesteps one current piece of evidence along these lines (calling it "indirect"!):

There is, for example, the evidence that brain size is correlated with intelligence, and that blacks have smaller brains than whites. But the brain size difference between men and women is substantially greater than that between blacks and whites, yet men and women score the same, on average, on I.Q. tests. Likewise, a group of people in a community in Ecuador have a genetic anomaly that produces extremely small head sizes — and hence brain sizes. Yet their intelligence is as high as that of their unaffected relatives.

Brain size doesn't correlated with intelligence so much as brain size relative to body/head size does, as the man/woman and Ecuador/relative comparisons attest, and as Stephen Jay Gould's The Mismeasure of Man argued. Women have smaller bodies to go with their smaller brains, and thus do not have lower IQs. The Ecuadorian folks have smaller heads and smaller brains.

By contrast, blacks have bigger bodies and similar-sized skulls, yet smaller brains, when compared to  whites -- at the very least, to say this doesn't create a genetic IQ difference, you'd have to re-think the relationships between head size, body size, brain size and IQ, because our current explanations don't lead in that direction. There's plenty of room in which to do this re-thinking, since the science is so unclear, but the article makes the brain-size evidence look a lot weaker than it is.

War games

I'm pretty sympathetic to the thesis that video games succeed where other mediums fail -- for example, many games produce the amazing visual experience that's lacking in modern "art." But if there's any area where video games are lacking, it's in plot, with only a few exceptions (Eternal Darkness is one). The stories and dialog are of the comic-book-for-13-year-olds vein, even in games rated for ages 17+.

So I think Glenn Reynolds's reader is wrong when he writes:

Did you know that Call of Duty 4: Modern Warfare for the video market has moved 3 million copies...that' s a 'box office' of 150 million.

And it's about the current war against terror...

So, if as Hollywood whines that the public doesn' t want Iraqi War movies, why is this selling so well, top of the rental lists, and ever so popular? At this rate it'll be the successful game companies, that gives the pubic what they want, who'll buy out the studios for their IP and name. Hollywood appears to have missed the impact of the technological shift as badly as MSM has. The public is getting the entertainment they crave, just not in the form that the old gatekeepers dispense.

Here's where this goes off course: "The public" doesn't buy "Call of Duty 4"; young, explosion-loving, military-admiring males do. It's possible that these same guys would see a movie in high enough numbers to make it worthwhile, but there's no reason to assume they would. Game-based movies are pretty risky to begin with.

Also, comparing a total sales figures between a $50 video game and a $10 movie ticket isn't exactly fair -- to match the two, you'd have to get five movie viewings for each game sold.