Paul Campos is a big fat idiot

Actually, that's not true. Unlike the title character of Al Franken's book, he doesn't seem to be particularly corpulent. But his "obesity myth" crusade is not just dumb, it is drugged-up-radio-talk-show-host dumb.

The prevalence of obesity among US adults has more than doubled in 25 years. Among US adolescents, it has more than tripled. If a change like that had been observed in prevalence of homosexuality, the scientific consensus would be very different regarding its origins (innate vs. acquired) and probably also regarding whether it is a normal variation or a health problem. But, as an empirical matter, there is no evidence that the prevalence of homosexuality has changed over time. Therefore, reality-based people, who value empirical evidence, do not pretend that obesity is analogous to homosexuality.

The Left vs. Larry Summers

It's another of those rare occasions when I have to disagree with Digby. I am puzzled with the Left's allergy to Larry Summers; one of its symptoms is obsessively scratching and digging up the 1991 World Bank memo about the possibility of selling toxic waste to Third-World countries. Says Digby:

Jonathan goes on to point out the unpleasant truth about such allegedly "out of the box" thinking --- that the people who reap the "benefit" of such things usually don't have to live in the putrid, polluted hellhole that's created by our toxic waste.

All I have to say in response is what I already wrote in a comment to a similarly-themed diary on Daily Kos, and an important part of it was the exact mirror image of Digby's thought - the people who scream that it is horrible and evil even to consider such ideas also don't have to share the fate of the poor people in the Third World:

In third world countries there are cities where children spend all day scavenging landfills. Perhaps there is unpolluted nature 20 miles away, but that does not help to make the lives of those children any safer, healthier, or more hopeful. Some more wealth in the country might, though - provided we can make sure it is actually spent on developing the country's economy and not on the leaders' luxury.

My current opinion (which is reality-based, so it may change with new information) is that toxic waste trade would be a bad idea, primarily because we could not effectively ensure that the money would be well spent. My educated but fallible guess is that Summers holds a similar view; my million-dollar bet is that he would similarly try to base his conclusions on reality and facts.

Look, some ideas seem yucky. But dissecting frogs is also yucky, and if you can't get over it, you can miss out on learning science. Part of maturity is that we should not let the yuck factor dictate our thought process and evaluation of ideas.

C'mon, people. All Larry is guilty of is bad taste.

Voters deserve better actuaries

Bragg is promoting his actuarial analysis of McCain and Obama again:

McCain would be the oldest president to begin a first term in office. By the end of a second term, Jan. 20, 2017, he would have a 24.44 percent chance of dying, compared with 5.76 percent for Obama, the firm estimates.

As far as I can tell, those numbers seriously understate the difference in the candidates' respective longevity prospects.

Let's start from the average mortality, given only the candidates' age and sex. McCain is 72 years and 32 days old and he will be 80 years and 144 days old on January 20, 2017. Using Social Security's life tables, his probability of dying before the end of his second term is 32.2%. Barack Obama is 47 years and 57 days old; his probability of dying by the same day, which in his case is age 55 years and 169 days, is 4.3%.

(Non-geeks may skip this paragraph: I used the 1940 cohort table for McCain and 1960 cohort table for Obama. Those are the closest to their birth years. Those choices favor McCain by the amount of mortality improvement from his 1936 cohort to the 1940 cohort. The difference is hardly negligible: using the 1930 cohort, we'd get 34.7% for the same ages, and linear interpolation yields approximately 33.2%, so the result I used is biased in McCain's favor by about 1 percentage point. Similarly, using 1960 cohort mortality for Obama introduces a slight - although almost negligible in this case - bias against Obama. One further geek note: I derived all survival probabilities by linear interpolation between nearest integer-year ages. That is more than accurate enough for the purpose of this analysis.)

Of course, there is more information available about the candidates, and Bragg lists some factors used:

He classified the Democrat as a smoker with minor upper respiratory problems, probably linked to his smoking. Obama announced in February that he was trying to quit smoking again, with the aid of nicotine gum.

"We don't consider you a nonsmoker until you stay quit for 12 months," said Brooks.

In the spring, the Obama campaign released a letter from the candidate's doctor declaring him to be in excellent health. He had very good cholesterol levels, his EKG was normal, his pulse was 60 beats per minute, and his blood pressure was an outstanding 90 over 60. Obama also exercises regularly.

But Obama has a family history of cancer. His mother died of ovarian cancer and his maternal grandfather died of prostate cancer. Obama's PSA screening test for prostate cancer showed no sign of abnormalities.

For the Republican, Brooks took into account a history of skin cancer, degenerative arthritis from his Vietnam war injuries, moderately high cholesterol, mild vertigo and that McCain is a former smoker who quit in 1980.

McCain allowed reporters to review eight years of medical records, more than 1,000 pages. They show that he is cancer-free, has a strong heart and is generally in good health. As a three-time melanoma survivor, his biggest health worry is a recurrence of that cancer. But he is closely watched by his dermatologist, and any future melanoma should be caught in time to be treated successfully. McCain maintains a healthy weight and blood pressure, and takes medication for his cholesterol.

That is hardly an unbiased account, and the statement that "McCain allowed reporters to review eight years of medical records" is, at best, barely true. In any case, the factors mentioned in the article should be worse news for McCain than for Obama.

Let's start with smoking. It is true that Obama wouldn't qualify for non-smoker rates if he applied for a life insurance policy today, but life insurance underwriting imposes rather crude discrete categories by necessity. (Verification is costly and the potential for cheating is high; for example, someone who smokes two packs a day could claim to smoke one pack a week.) This individualized analysis can do much better than that. Obama's quitting has not been entirely successful, but he is clearly closer to a former smoker than to a current one. McCain stopped smoking years ago, but he used to smoke two packs a day for 25 years. So they have a similar smoking history and quit at a similar age. By itself, this factor would make each of them more likely to die than an average man of their age. The effect is probably greater for Obama mainly because fewer men of his age are smokers, so average mortality for his cohort is based on a higher percentage of non-smokers. I would be curious to see what factors Bragg applied to account for smoking history.

(Another note for wonks: Insurers generally charge smokers double or even higher rates than nonsmokers, and that is soundly based on experience, but those factors apply to a baseline of the insured population, i.e., to the people who have passed other underwriting hurdles. For example, by the Society of Actuaries' 90-95 Basic Select tables, a male smoker of Obama's age would have about 3.5% chance of dying in the next 8 years, which is better than the average from the Social Security tables. Similarly, a smoker of McCain's age would have 23% chance of dying in the next 8 years, again better than in the SSA tables. Another thing to keep in mind is that, in insurance underwriting, smoking also serves as a proxy to other risky behavior, which means that not all of the excess mortality of smokers is caused by smoking.)

The candidates' fitness balances their smoking history. Both candidates seem to have healthy hearts, and Obama's pulse and blood pressure cited by Bragg are impressive. Obama is thin and McCain's weight is normal. They both seem significantly more fit than average men of their respective ages. Fitness-related mortality patterns are far less well known than smoking-related ones, but my guess would be that both candidates make up in fitness about as much as they lose from smoking history. Additionally, both are married and have (as far as we know) healthy spouses, which also improves their longevity prospects. Not to mention that both have access to best available health care.

So far, very similar adjustments to age/sex baseline apply to both candidates, but the rest is all bad news for McCain. Melanoma is a serious type of cancer, prone to metastasizing that is hard to detect and treat. It is true that McCain has been free of symptoms for 8 years and that it improves his prognosis, but the fact that he's had 4 episodes of melanoma, and that the last one was over 2 mm deep, raise additional concerns. For lesions like his last one, 5-year survival rate is 63-79% and 10-year 51-64%. He has survived for 8 years, so the greatest risk is behind him, but he is not out of the woods:

“With melanoma, a patient is never completely clear,” said Dr. Shapiro, the N.Y.U. expert.

If melanomas do recur, standard treatment options are limited for many to surgery and a difficult form of chemotherapy. The chances of long-term survival diminish.

Precise estimates aren't available, but it is hard to see how McCain's chance of dying from this one cause alone would be less than 10% over the next 8 years.

Another issue for McCain is the long-term effects of maltreatment by the Vietcong. Five and a half years of injuries, torture and malnutrition certainly have health consequences. Quantifying the effect is difficult, but that's not a good reason to ignore it altogether.

In summary, there is little reason to think that Obama's probability of dying in the next 8 years exceeds that of an average man of his age - 4.3 percent. In fact, it is probably less than 3.5 percent, the number based on life insurance policy experience. On the other hand, I don't see how McCain's probability of dying in the same period would be much less than one-third. In other words, McCain is at least 9 times as likely to die in office as Obama. Bragg tells us it is not quite 4.5 times. Unless he publishes more details about the calculation and the assumptions, I can't see how his results could be justified.

UPDATE: It is probably wrong to focus on survival to the end of second term. Incumbency is an advantage in an election, but we don't elect a President for 8 years, and we would (hopefully) have updated health information before the next election. Going back to the baseline (Social Security tables), a man of McCain's age has 15.4% chance of dying before January 20, 2013, and a man of Obama's age has 2.0% chance of dying in the same period. By the way, the shorter the period we look at, the more significant a factor McCain's cancer is, because the probability of recurrence goes down the longer he's already survived.

The rumor hoax

Beneath the blatant McCain lies that Obama and his campaign are smearing Sarah Palin, there is a much thicker and stickier level of deception, whose theme is that malicious false rumors about Palin circulate on the Internet. That bullshit pretense of debunking rumors is perhaps more dangerous than the obviously mendacious attack ads, because it appears calmer, less confrontational, and more credible. Rather than attacking a named opponent, it defends the candidate from an amorphous virtual mob of accusers. By a sleight of hand, it transplants a meme that fits in a different context - "innocent until proven guilty" - and conjures up an illusion that Palin is on trial (and a politically motivated one to boot) and that we, the voters, are expected to act like a jury and acquit if there is any reasonable doubt.

That's bullshit, but its stealth power is such that it has infiltrated even some brand-name bullshit detectors, such as FactCheck.org.

Here is an example of how ordinary people propagate this meme, from a recent comment left on this blog:

It is true that, while scrutinizing politicians, we should hold them suspect and investigate any evidence that might shed light on their career or character. But in the end, you must hold them innocent until proven guilty. There is no moral justification for assuming them guilty until proven innocent. Considering the enormous amount of false accusations against Palin (see a debunking of vicious internet rumors against her here at factcheck.org), the burden of proof is on those making the allegations. Until they prove their case or you yourself find corroborating evidence from another source, the voter--and any intelligent being--must dismiss the allegations as lies and slander.

Note the structure of the argument:
1. "Innocent until proven guilty"
2. "False accusations" and "vicious rumors"
3. Therefore, the juror voter must acquit ignore the allegations.

It is relatively easy to explain why steps 1 and 3 are bogus. The analogy between voters and jurors in a civil case would not be a bad one, but the argument relies on the specific features of a criminal trial, and that makes the analogy untenable. In a civil case the jury decides between two parties who are a priori on equal standing, and who would gain similarly from a win and suffer similarly from a loss. That is a lot like choosing between two political candidates. The jury simply decides whose case is stronger. But in a criminal trial, the parties are in a hugely asymmetric starting position, with one party (the state) having all the power and the other (the accused) facing all the risk. Those conditions, which in no way resemble elections, are the reason for presumption of innocence and a high threshold for proving guilt. Asking voters to behave like a criminal jury makes no sense whatsoever.

The structure of the argument is thus debunked and the voters should revert to their natural standard of the preponderance of evidence. Step 2 is still relevant, however, because the information in and about those rumors can tip the scale for some undecided voters. Thus, the rest of this article will examine the claims that the accusations are false and rumors vicious.

Let's be clear: the only candidate in this race about whom there is heavy traffic of vicious and false internet rumors is Barack Obama. I will not repeat any of those rumors here because they don't deserve the minimum level of respect that even the harshest criticism conveys. They have been thoroughly debunked and refuted, and should now be silenced. Nothing comparable to that sludge is being thrown at Sarah Palin. Naturally, some rumors about her are false and some are exaggerated, but that can be said of practically every public person. If rumors about Palin exhibit any unusual pattern, it is in how much truth they may yet turn out to contain.

As the commenter noted, FactCheck.org has compiled a list of "false Internet claims and rumors" about Palin. I have already written about problems with FactCheck.org's coverage of this campaign, and I regret to inform you that they have pooped their pants again. (Why is that happening? I don't think they are intentionally biased in McCain's favor. Rather, they are not immune to the "balance" anxiety of American journalism: when lies are grossly unbalanced, journalists feel compelled to restore the balance by applying uneven standards. But that topic deserves its own post, which I promise will be coming soon.) Let's examine the five items on the list and FactCheck's analysis.

#1: Special needs education

Palin did not cut funding for special needs education in Alaska by 62 percent. She didn’t cut it at all. In fact, she increased funding and signed a bill that will triple per-pupil funding over three years for special needs students with high-cost requirements.

As far as I can tell, the rumor is indeed false. But is it vicious? It is not defamatory: it ascribes to Palin a legitimate (although, I suppose, unpopular) policy position. And it is unlikely that it was launched maliciously, as FactCheck.org traced its origins to what easily could have been an honest mistake:

Those who claim that Palin cut special needs funding by 62 percent are looking in the wrong place and misinterpreting what they find there. They point to an apparent drop in the Department of Education and Early Development budget for special schools. But the special schools budget, despite the similar name, isn't the special needs budget.

By the way, it is possibly misleading to say that she increased funding. The legislature increased funding; she merely signed it. This is not nitpicking, nor is there a symmetry. As governor, she has "line-item" veto power, so she really can cut funding for specific projects, but she cannot singlehandedly increase it. Unless she took some initiative to enact the increase (which she may well have, but no evidence for it is supplied), FactCheck.org has exaggerated a bit in the exonerating statement.

Bullfighter's verdict on this rumor: false, but neither personal nor vicious. Merely erroneous and unremarkable.

#2: Banning books

She did not demand that books be banned from the Wasilla library. Some of the books on a widely circulated list were not even in print at the time. The librarian has said Palin asked a "What if?" question, but the librarian continued in her job through most of Palin's first term.

Here FactCheck errs big time, debunking a straw man and missing the point, with the result of misleading readers.

The relevant story here doesn't involve actual banning of books, but a loyalty test for the librarian. The allegation is that, when she took over as mayor, she asked the librarian how she would feel about a request to remove objectionable books from the shelves. The librarian answered that she would not remove any books, and that was apparently the wrong answer, because Palin subsequently fired her (although she relented when people protested). In the in-depth analysis, FactCheck confirms those facts and even Palin seems to have no objections:

Palin told the Daily News back then the letters were just a test of loyalty as she took on the mayor’s job

The real issue is that such a loyalty test - requiring the librarian to put loyalty to authority above her professional duty and possibly the law - is completely inappropriate, and there is no legitimate reason for the mayor to ask that question. Its chilling effect may be sufficient to raise First Amendment concerns, and it speaks a lot about Palin's attitude to public service.

FactCheck.org acted irresponsibly by focusing on derivative rumors - purported lists of banned books pulled out of some prankster's ass. I don't even believe those rumors are widespread; I haven't seen any such list although I dig through news and blogs excessively. But by prominently debunking some amateur's nonsense and burying the relevant facts where few people will read them, FactCheck contributed to the impression that the entire issue of Palin's censorship tendencies is a hoax.

Bullfighter's verdict: FactCheck committed the equivalent of breaking a Ming vase while trying to dust it. Despite some ridiculous pranks inspired by it, the relevant main story is true.

#3: AIP

She was never a member of the Alaskan Independence Party, a group that wants Alaskans to vote on whether they wish to secede from the United States. She’s been registered as a Republican since May 1982.

As I noted before, this gun is still smoking. Palin has been "cleared" on the narrow issue of her own membership (which was never a mere rumor - the allegation was made by AIP's top officials), but that is an irrelevant bit in a potentially extremely damning case. FactCheck's mistake is similar to that in #2, but far more dangerous, for two reasons. First, this is by leaps and bounds more serious issue than local library censorship; the worst case here may involve flirting with treason. Second, the "debunking" doesn't merely wander into the irrelevant, but consciously emphasizes the only detail of the story where evidence favors Palin and hides or ignores everything else. And, by the way, her husband's membership may be as relevant as her own.

Bullfighter's verdict: FactCheck fucked up.

#4: Endorsing Buchanan

Palin never endorsed or supported Pat Buchanan for president. She once wore a Buchanan button as a "courtesy" when he visited Wasilla, but shortly afterward she was appointed to co-chair of the campaign of Steve Forbes in the state.

So she never endorsed Buchanan, but she contributed to the appearance that she did. In her own words (quoted deep down in the FactCheck article):

As mayor of Wasilla, I am proud to welcome all presidential candidates to our city. This is true regardless of their party, or the latest odds of their winning. When presidential candidates visit our community, I am always happy to meet them. I'll even put on their button when handed one as a polite gesture of respect.

Really? Regardless of the party? She would welcome the candidate of the Communist Party? How about the Nazi Party? If we take her explanation seriously, it raises some interesting questions.

Now it is true that the meme of "Palin for Buchanan" is potentially very damaging - Buchanan is widely regarded as an anti-Semite - so one could suspect its malicious origins, were it not for the fact that it was Pat Buchanan himself who launched it nationally. While some Democrats have used it (e.g., Congressman Wexler), no one can say that a Democrat or a liberal started it.

#5: Creationism

Palin has not pushed for teaching creationism in Alaska's schools. She has said that students should be allowed to "debate both sides" of the evolution question, but she also said creationism "doesn't have to be part of the curriculum."

This doesn't even make sense; it is self-contradictory. If she said that students should be allowed to "debate both sides", then, by definition, she supported teaching creationism. So what is FactCheck's point? That "supported" doesn't necessarily mean "pushed for"? Did anybody use those words? Is that worth FactCheck's attention? Please.

Oh, and what does FactCheck say in the detailed analysis? Basically, that their own summary is full of shit:

On Aug. 29, the Boston Globe reported that Palin was open to teaching creationism in public schools. That's true. She supports teaching creationism alongside evolution, though she has not actively pursued such a policy as governor.

This is embarrassing. FactCheck says FactCheck is wrong.

Bullfigher's verdict: The "rumor" is true, and FactCheck shot itself in the foot.

Scoreboard: of the five "debunked" rumors,
one is completely true,
one is generally true (and well-documented), but one detail turned out to be false despite testimonies,
one is based on a true story, but FactCheck focused on a prank inspired by it,
one is false but based on an understandable mistake,
and one is false and potentially harmful, but came from a conservative source, and Palin herself contributed to its creation.

There has actually been another rumor out there, not mentioned by FactCheck, which might have a much stronger claim to the "vicious rumor" title than any of those five. That is the rumor that Palin's youngest child was actually her daughter's, and that she faked pregnancy to cover up her daughter's. The McCain-Palin campaign blamed this one on "liberal bloggers":

ST. PAUL, Sept 1 (Reuters) - The 17-year-old daughter of Republican vice presidential candidate Sarah Palin is pregnant, Palin said on Monday in an announcement intended to knock down rumors by liberal bloggers that Palin faked her own pregnancy to cover up for her child.

Actually, that wasn't a quote, that's Reuters drinking the Republican Kool-Aid. The campaign was more insidious, and make sure Obama's name got mentioned although there was no logical place for it:

"The despicable rumors that have been spread by liberal blogs, some even with Barack Obama's name in them, is a real anchor around the Democratic ticket, pulling them down in the mud in a way that certainly juxtaposes themselves against their 'campaign of change,'" a senior aide said.

Yes, the rumor was all over the Internet during the Labor Day weekend, but its treatment on the liberal blogs I read ranged from suspicion to dismissal, and many ignored it completely. There were several diaries posted on Daily Kos that perpetuated the claim, but every one of them received negative comments, warning about the lack of evidence or implausibility of the story; there were also diaries debunking the rumor. In other words, this was never a story that got significant traction in the liberal blogosphere.

There were speculations on Daily Kos that the rumor was planted by the Republicans as a bait to accuse librals/Democrats/Obama of smearing Palin. In light of the announcement of Bristol's pregnancy, that seems very plausible. They needed to create a context in which the pregnancy (which couldn't be hidden until November) would be announced as something relatively favorable. That doesn't necessarily mean that the Republicans planted the rumor (I've also heard that it had been all over Alaska since Trig Palin's birth), but it was definitely convenient to them.

What is rarely mentioned is that Palin's own behavior helped build the rumor. She kept her pregnancy secret until the seventh month, flew from Texas to Alaska after her water broke, didn't tell the airplane crew that she was in labor, and returned to work unusually fast after giving birth. None of those claims are disputed, and the source for most is Palin herself. There is a related rumor about Bristol missing several months of school due to mono, but I haven't seen any supporting evidence for it, and without it the story didn't work. But what made the rumor even more implausible was that a 44-year old mother has some 30 times greater risk of having a Down syndrome baby than a 17-year old. There were too many holes in that rumor even before the announcement (which by itself didn't actually refute anything). But Palin's adventurous travel from Texas to Alaska with leaking amniotic fluid, unless it is just another of her serial lies, raises questions about her judgment and responsibility.

So, the final verdict: there was one short-lived rumor that could have qualified as "vicious", but it never really caught on, it might have been planted, and it was only possible because of Palin's inexplicably odd behavior.

I'd like to know which major-party candidate for President or Vice President was the subject of fewer false accusations and vicious rumors than Sarah Palin.

Dude, where's my 14 million dollar house!?

From the department of I-told-you-so:

Wait a minute. Who will buy those houses? At 6% annual interest rate, a 30-year mortgage on an average home would require payments exceeding three-quarters of an average household's income. And that's just mortgage payments - no property tax, insurance, maintenance, or utilities. Even at the entirely unrealistic zero interest, mortgage payments would equal 36% of income. Prices can be astronomical in a limited area, where only the region's elite can afford to live, but the study refers to the entire Washington Metropolitan Area, which, according to the article, will then span from Baltimore to Richmond and have a population of 9.9 million. If only the top 5-10% can afford housing in the area, where will the other 9 million live? There is a violation of the law of supply and demand in the study's results.

That study is yet another example of the dangers of extrapolating exponential growth rates over long periods. If you calculate the annual growth rates implicit in the study's results, they look reasonable: housing prices increasing 7% per year, and incomes 4.6% per year. Assuming 3% inflation, the real (net of inflation) rates are 4% and 1.6%. I might use those numbers myself if I had to predict prices and earnings 2-3 years from now.

The problem is that the difference in growth rates of 2.4% compounds to a factor of more than 3 (in other words, a difference of over 200%) over 50 years. What makes sense over short periods doesn't necessarily make sense in the long run.

On the bright side, we will not all be Pentecostals by 2075.

Presidential terms and actuarial errors

Atlanta Journal-Constitution reports that the actuarial firm John M. Bragg & Associates has estimated the healthy life expectancy - average remaining life free of Alzheimer's or other impairments requiring an assisted living facility - for John McCain and Barack Obama. Bragg gives McCain a health expectancy of 8.4 years, and Obama 21.9 years, and offers the following conclusion:

“Either candidate can be expected to serve two full terms, without age or health being an issue,” said John M. Bragg, the firm chairman.

John Aravosis points out that Bragg's numbers don't add up:

The actuarial (sic) says McCain has 8.4 "healthy" years left. He mistakenly drew the conclusion that McCain would therefore be healthy through two terms in office, thinking that eight years from now is the end of McCain's term. That's incorrect. The end of the term is in 8 years 5.5 months from now. Statistically, that means McCain won't make it through two terms as a "healthy" president. By healthy, he means “the person does not require the care provided by an assisted living facility and is free of Alzheimer’s disease.”

By my back-of-the-envelope calculations, that means McCain wouldn't even be able to complete two full terms in office. His time runs out on December 30th or so of 2016, a good three weeks before the new president would be sworn in. So that means, statistically speaking, before the end of two terms, we should expect President McCain to have to be moved to a retirement home because he'll no longer be able to care for himself, and we should expect that he'll already be suffering from Alzheimer's.

Aravosis is correct in noting that 8.4 years from now does not give the new President (whoever it is) two full terms. His explanation of what that means is a little sloppy, but the end result is most likely correct. The issue is what it means that "we should expect" McCain (not) to be healthy and alive by the end of the two terms. I assume that Aravosis means "it is more likely than not", but that doesn't follow so simply from the published statistic.

Mathematical expectation is the theoretical mean, not median. What it means is the following: if we had a thousand men of the same age and other relevant characteristics as John McCain, we follow them all until they die and note how long each lives, and then we sum up all of their times from now until death, and divide the result by 1000 (the number of them), we will get something very close to 8 years, 146 days.

It does not mean that 500 of them will live longer than 8.4 years and the other 500 shorter. That would follow only if the remaining lifetime were distributed symmetrically, for example, if it followed the bell-shaped normal distribution. But that is not the case: all remaining lifetimes must be greater than zero, but there is no reason some of them couldn't be 30 years or more. The expectation (8.4 years) is obviously not in the middle of the range, so the distribution is skewed (asymmetric).

Now it turns out that, in most distributions of this kind (with a "tail" on the right), the median is less than the mean. If the median healthy survival is less than 8.4 years, it would mean that fewer than 500 of the initial 1000 "McCain clones" would have more than 8.4 years of healthy life - and, obviously, even fewer would have 8.46 or so years needed to complete two terms in office. So Aravosis made a correct statement, after all.

If Aravosis is correct, Bragg must be incorrect. It is not possible to say, based on Bragg's own numbers, that McCain "can be expected to serve two full terms, without age or health being an issue". Because the median is almost certainly lower than the mean, it would not be true even if the expected healthy life were somewhat longer, say 8.5 years, extending beyond two terms. It would still imply that McCain is more likely than not to die or become seriously impaired before the end of the second term.

But this error in arithmetic is not the most bothersome part of Bragg's statement. After all, if all the critique amounted to were nitpicking about chances being 49% rather than 51%, it would be rather academic. I see a far more serious problem in Bragg's choice of risk measure.

Suppose for a moment that Bragg's arithmetic was right, and that McCain could be expected, albeit barely so, to be alive and healthy on January 20, 2017. Suppose his chances are 55%. That's a generous "improvement" of Bragg's estimate, but it still means a 45% chance he would be dead or incapacitated. Would most people be comfortable with a president facing those odds? Would most people, upon hearing that number, characterize a potential McCain presidency as "without age or health being an issue"? I doubt that. From the risk management point of view, Bragg has cited an almost useless statistic.

John M. Bragg is not just any actuary. He was President of the Society of Actuaries. That, however, was a long time ago, when the US President was named Gerald Ford.

Dog bites man: miles per gallon edition

A Duke University study, published in Science and reported in the Consumer Reports, found that miles per gallon are misleading and that consumers would make better decisions if fuel consumption were posted in gallons per mile.

Well, duh. Shouldn't that be obvious?

Is it any surprise that people calculate better with direct quantities than with inverses? Miles per gallon is an inverse measure of the cost of fuel, so one doesn't have to be a rocket scientist to figure out that consumers will have more trouble making rational decisions based on that measure than based on a direct measure of fuel consumption, such as liters per 100 kilometers, which is used in Europe and pretty much the rest of the world.

Most people don't realize (at least not immediately) that driving 45 mph from Startington to Endington (distance: 60 miles) and 80 mph on the way back takes more time than driving 60 mph both ways. But they do realize that a 80-minute trip and a 45-minute trip together take longer than a two-hour trip. Similarly, people don't realize that going from 12 to 16 mpg is a greater saving than going from 24 to 32 mpg, but they would recognize immediately that going from 20 to 15 l/100 km is more significant than going from 10 to 7.5 l/100 km. Elementary, my dear Watson!

Why centrist voters elect extreme politicians

Andrew Gelman notes that, on a one-dimensional scale of ideological positions,

elected representatives are generally more extreme than voters.

Moreover, geographic polarization of legislators is much more pronounced than that of the voters:

I am not sure what wisdom we are supposed to gain from those facts, but I see some serious problems with the analysis, even if we grant that measuring ideology on a one-dimensional scale is itself unproblematic.
How meaningful is a comparison between voters' survey responses and legislators' votes? I am not asserting a "words vs. deeds" distinction here; voting is a form of speech, especially votes are publicly known, as legislators' votes are. But legislators are actually held responsible for their votes and expected to be consistent. The public, regardless of ideology, tends to like people with strong principles and dislike "flip-floppers". As much as we sometimes think of them as stupid or ignorant, politicians are, on average, unquestionably better informed and have thought more thoroughly about issues than the general public. We should expect their views to be more consistent than voters' views.

Now, there are rarely consistent "moderate" or "centrist" positions on most issues. Political moderates usually hold "left" positions on some issues and "right" positions on others. In George Lakoff's words, they are biconceptuals:

The pressure to dissemble comes from certain commonplace myths about swing voters and the "center." So for starters, let's put to rest the notion of the political or ideological "center"---it doesn't exist. Instead, what we have are biconceptuals---of many kinds.

A more cynical view would be that the "centrists" are inconsistent, confused, or hypocritical. While it would probably be considered unfair to characterize an ordinary private citizen that way, most politicians would very quickly (and perhaps rightly) earn those labels if their voting patterns resembled the survey responses of "centrist" voters.

The next question is why a centrist electorate would elect a polarized legislature. An obvious explanation is the two-party system and electoral districts drawn to put most Congressional seats safely under control of one or the other party. I would agree that those features of our political system increase the polarization of Congress, but the graphs strongly suggest that such an explanation is woefully incomplete.

First, the Senate seems to be no less polarized than the House, and geographically even more so, which belies the safe districts part of the argument. Second, there seems to be very little difference between voters in "battleground states" and "Democratic states", but a vastly different distribution of elected officials, particularly senators. As the states are grouped by the results of Presidential elections, this observation is by no means tautological.

The graphs tell us that very similar electorates consistently elect ideologically very different politicians. A likely explanation is that the survey responses do not measure overall ideological positions accurately. Perhaps voters put significantly different weights on different issues, which makes them prefer different politicians despite having similar (unweighted) average survey responses? That's a conjecture, not a conclusion; the point is that the analysis presented so far is not satisfying and it generates more questions than it answers.

Framing, Damn Framing, and Statistics

I am not the least bit opposed to framing in principle. However, framing gurus should take care not to feed the (fairly common) opinion that framing equals paltering. Matt Nisbet fails that task with this graph:


Nisbet is showing this to support his thesis that there are "two Americas" and that only the one that agrees with Al Gore politically has become more concerned about climate change in recent years. But that is not a valid reading of the graph unless the relative numbers of the Democrats and Republicans have been stable over the period, and data from the same source suggest that they haven't. There are fewer Republicans now than a few years ago. If we assume that most of the party-switchers are moderates and that most moderates are concerned about climate change - and both assumptions seem reasonable - then the remaining loyal Republicans are, on average, more partisan and more dogmatic than before, and the divergence of the two lines in the graph just illustrates that corollary.

There are more conclusions that can be drawn from that graph, but none of them is about Al Gore's ineffectiveness.

Do Religious People Give More, Or Just Lie More?

PZ Myers responds to an article by Jonathan Haidt which starts out great, but segues into a rant against "New Atheists". It is interesting to read both articles as well as comments. One of the many points of contention was this:

Haidt says that "surveys have long shown that religious believers in the United States are happier, healthier, longer-lived, and more generous to charity and to each other than are secular people,"

PZ offers plausible, but speculative, counterpoints before pointing out that such results, even if true, are irrelevant to the issue of whether religion is true. He also correctly points at the inconsistency of justifying Christianity (which is the de facto dominant American religion) on hedonistic and utilitarian grounds.

Still, I was curious about those surveys, particularly because Haidt accused none other than Daniel Dennett, the most cautious of the "New Atheists", of willfully ignoring evidence and of thinking morally under the guise of thinking scientifically:

I have italicized the two sections that show ordinary moral thinking rather than scientific thinking. The first is Dennett's claim not just that there is no evidence, but that there is certainly no evidence, when in fact surveys have shown for decades that religious practice is a strong predictor of charitable giving. Arthur Brooks recently analyzed these data (in Who Really Cares) and concluded that the enormous generosity of religious believers is not just recycled to religious charities.

Thankfully, a commenter critical of PZ provided a link to Brooks' own summary of that study. Another commenter linked to a mild criticism of Brooks on The Volokh Conspiracy. But there is a lot more to criticize!

Brooks' definition of "secular", based entirely on infrequent religious service attendance, includes 26% of the total sample. The most optimistic numbers I've seen for nonreligious in any poll are around 14%, which means that about half (and possibly more) of the so-called "secular" were in fact religious people who rarely or never attend services. Those probably differ significantly from the nonreligious, so which subgroup is driving the results?

ReligiousTolerance.org (RT) has an analysis of false self-reporting of attendance cites sources that estimate that, although about 40% Americans report that they attend services weekly, only 20% actually do. Brooks counts 33% of his sample among the "religious" based on weekly attendance; it would thus appear that a third of those are only included because they lied.

Even more interestingly, the RT page cites Barna Group data that, while 17% report giving 10% or more of their income to their church, only 3% actually do. So we know from previous studies that self-reported giving is exaggerated. The usual explanation is that people say they do what they think they should do, not what they actually do. If the religious have a stronger sense that they should give more than they do, they will exaggerate their giving more.

I think that's enough to invalidate any conclusions from Brooks' study, but, as a general rule, whenever you see a policy paper, don't forget to check the sources and the context. This was published by the Hoover Institution, a conservative think tank. It is true that Hoover is more credible than Heritage and AEI - not everyone at Hoover is a hack - but keep in mind that Dinesh D'Souza is a fellow there. As a further clue to author's bias, note that Brooks approvingly quotes Robert Bork and Irving Kristol. I must say I would have more confidence in honesty and objectivity of a Vatican study on the same topic.

In light of such glaring problems with Brooks' study, I wonder how Haidt can honestly write

These data are complex and perhaps they can be spun the other way, but at the moment it appears that Dennett is wrong in his reading of the literature.

He was addressing Dennett's statement that "[c]ertainly no reliable survey has yet been done that shows" that "as a group atheists and agnostics are [less] respectful of the law, [less] sensitive to the needs of others, or [less] ethical than religious people." Well, I have proven above that Brooks' study is not reliable, so Haidt is the one not thinking scientifically when he uses it as evidence against Dennett.

Dismal (but getting used to it) Science

Most modern macroeconomic models are based on the paradigm of ultrarational and super-far-sighted economic agents (that's economese for "people") who act to maximize their expected lifetime utility (which is quantified happiness, more or less). Utility is usually modeled as an increasing function of consumption (not TB, but how many toys you get to buy) and leisure time (important if people have a choice of how much to work). For ease of computation (and, usually, for lack of strong evidence to the contrary), there is often a simplifying assumption that utility is time-separable and additive, which means that your lifetime utility is just the sum of your utilities in each year (perhaps discounted by some impatience factor). That is, your happiness this year depends only on how much you buy this year, not, for example, on how much you had last year and got accustomed to it; and it contributes to your lifetime happiness independently of what happens in any other year. Everyone knows the model is oversimplified, but at least it is as objective as can be... isn't it? Maybe not:

folks on the left get used to money, but not status and the reverse for folks on the right. (...) the fact that the happiness-effects of various things seem to be mediated by ideological leanings seems to basically ruin the prospect of using happiness research as a neutral, scientific way of assessing policy. It may just end up sort-of-usefully reminding us that one group may like a certain policy and another group may not simply because it makes one group feel better and another group feel worse.

Holy Wotan and Fricka! If this German study and Wilkinson's interpretation, above, are correct, any analysis of well-being based on the time-additive-utility-for-consumption model will measure the well-being only of politically right-leaning agents. Policies that aim to maximize social welfare (that's well-being, not dole) will, in fact, maximize the welfare of the righties and may well screw the lefties.

Well, I feel guilty: of course I use those models. But at least I always thought (and said) that welfare analysis in those models was fishy business. I think I can convince the jury that my transgressions have been mere misdemeanors.

There may be a less devastating interpretation, according to Quiggin:

Rather than duplicate all the excellent discussion, I’ll offer the possibility that those on the right may not be so different from the rest of us as they seem to be at first sight. Money is valued because it provides access to goods and services, but it can also be used to keep score in a competition.

In other words, in the long run, everybody cares only for status, but righties measure status by income, while lefties perceive status along some other dimension. (Who has higher status? An endowed full professor of philosophy making $110,000/yr or a starting assistant professor of finance making $125,000/yr?) This makes a lot of sense. If Quiggin is right, the paradigm isn't biased (it is just wrong for everyone), but the practical results would still have right-leaning bias: it is not crucial how the alignment of conservatives with the model assumptions arises.

Thou Shalt Not Extrapolate Exponential Growth Rates

If you think housing in the DC area is expensive now, just wait 50 years:

The findings, discussed at a forum sponsored by the Metropolitan Washington Council of Governments, show that the price of the average home in the area will grow to $14 million in 2057 from today’s average of $477,000.

Should we take this seriously? After all, I saw it in a free newspaper. But it quotes a real study, and its author, a professor at George Mason University. Let's read a little more:

Researchers predicted, however, the average household income would only climb to $1.3 million from today’s $137,000 during the same period.

“We already have an affordability problem,” said George Mason University professor Stephen Fuller, who calculated the estimates. “But this is really scary. It is going to take 11 times the average household income to afford the average-priced house.”

Wait a minute. Who will buy those houses? At 6% annual interest rate, a 30-year mortgage on an average home would require payments exceeding three-quarters of an average household's income. And that's just mortgage payments - no property tax, insurance, maintenance, or utilities. Even at the entirely unrealistic zero interest, mortgage payments would equal 36% of income. Prices can be astronomical in a limited area, where only the region's elite can afford to live, but the study refers to the entire Washington Metropolitan Area, which, according to the article, will then span from Baltimore to Richmond and have a population of 9.9 million. If only the top 5-10% can afford housing in the area, where will the other 9 million live? There is a violation of the law of supply and demand in the study's results.

That study is yet another example of the dangers of extrapolating exponential growth rates over long periods. If you calculate the annual growth rates implicit in the study's results, they look reasonable: housing prices increasing 7% per year, and incomes 4.6% per year. Assuming 3% inflation, the real (net of inflation) rates are 4% and 1.6%. I might use those numbers myself if I had to predict prices and earnings 2-3 years from now.

The problem is that the difference in growth rates of 2.4% compounds to a factor of more than 3 (in other words, a difference of over 200%) over 50 years. What makes sense over short periods doesn't necessarily make sense in the long run.

For a related example, consider health care costs. Their share of GDP grew from 7.2% in 1965 to 16% in 2005, at an average annual rate of 2.7%. If that trend continued for another 50 years, health care would account for 60% of GDP in 2055. Keep in mind that health care is itself a sector of the economy, so its product is counted in the GDP, and if it makes up 60% of GDP, it means that it is one-and-a-half times as big as the rest of the economy combined. If that doesn't make the absurdity of the result obvious, try to ponder what would happen just 8 years later, when health care expenditures would exceed 100% of GDP.

Similarly, if you looked at the rate of growth of market capitalization of Nortel or Enron in the years before their respective stocks crashed, and extrapolated those rates into the future, you would conclude that those companies would own everything in North America at a time not too far into the future.

Or take population groups. Population growth in Muslim countries has been higher than the world's average, so Islam has been increasing its share, which currently stands at about 19% of the world's population. According to some estimates, the number of Muslims has been growing approximately 0.6 percentage points faster, annually, than the world's population. At that rate, by the end of 24th century, everyone in the world will be Muslim. The only problem is, Pentecostalism, with about 2% of the world's population as its adherents, is growing about 6% faster than the world's population, so by 2075, everybody in the world will be Pentecostals.

A more cheerful extrapolation shows that in just 10 years, every computer in the US will be a Mac.

The Mismeasure of Bias

This is one of the most astute critiques of a methodologically flawed paper that purports to measure ideological bias in the media. Nyhan's main points are:

(1) Technocratic centrist to liberal organizations like Brookings and the Center on Budget and Policy Priorities tend to have more credentialed experts with peer-reviewed publications than their conservative counterparts. This may result in a greater number of citations by the press, which seeks out expert perspectives on the news, but not more citations by members of Congress, who generally seek out views that reinforce their own.

(2) The Groseclose/Milyo methodology doesn't allow for differential rates of productivity in producing work of interest to the media or Congress between organizations. To the extent that a think tank is better at marketing itself to the press than Congress (or vice versa), it could skew the results.

He quotes other sources, too, and this argument from Media Matters is particularly convincing:

For instance, according to their data, the National Association for the Advancement of Colored People (NAACP) is the third most-quoted group on the list. But stories about race relations that include a quote from an NAACP representative are unlikely to be "balanced" with quotes from another group on their list. Their quotes will often be balanced by quotes from an individual, depending on the nature of the story; however, because there are no pro-racism groups of any legitimacy (or on Groseclose and Milyo's list), such stories will be coded as having a "liberal bias."

And there are more general issues that would remain even if these details were somehow fixed. The very notion that some average (median or whatever) of population's views is "unbiased" is unfounded; and, even if the population's median view were deemed "unbiased" by definition, there would still be a big leap from the median member of Congress to the median voter, and another from the median voter to the median member of the population.

Too bad Andrew Gelman's endorsement of Brendan Nyhan's critique is only lukewarm, even though he realizes that "bias" is a misnomer for the quantity that G&M measured. More generally, it is sad that so often people with great analytical skills fail to appreciate the world beyond the limitations of a mathematical model.