If We Burned All Our Fossil Fuel

If we burned all the coal, oil and gas that’s left in the ground, we’d melt Antarctica and global sea levels would rise as much as 60 meters (200 feet) over the next ten thousand years. Coastal cities from New York to Shanghai would wind up deep underwater.

(One of multiple news stories reporting on a newly published journal article.)

That sounds scary—if you miss "over the next ten thousand years."

The article the news story is based on is webbed. It gives an estimate of the consequences of burning all of Earth's fossil fuel over the next few centuries. The conclusion is that "Antarctica is projected to become almost ice-free with an average contribution to sea-level rise exceeding 3 m per century during the first millennium." Figure 1d from the article shows a rapid rise, close to forty meters in the first thousand years, gradually tapering off thereafter.

Three meters a century is considerably faster than the current rate of rise—not surprising since it would be driven by a CO2 concentration about eight times the current level. One way of getting a feel for how serious it would be is to convert it into a rate at which coastlines move inward, assuming no diking. The rule of thumb for that is about a hundred meters shift for every meter of rise. So three meters per century of SLR implies coastlines shifting in by about three hundred meters a century, more in some places, less in others, but well short of the catastrophe implied by "coastal cities deep underwater."

Another way of looking at it is in terms of what could be done via diking. The lowest city in the Netherlands, a country with centuries of experience protecting land below sea level, is more than six meters below sea level. With two centuries to do it in, I expect New York or Shanghai could match that.

Another conclusion of the article is that the Antarctic would end up almost ice free, but it is not clear why that would be a bad thing. We are currently in an ice age, defined by the existence of ice on the poles. There have been earlier ice ages, but for most of the history of the Earth, including most of the period with living creatures and even most of the period with mammals, the poles have been free of ice.

Figure 1c shows the estimated effect on average global temperature—an increase over about a thousand years of a little over 10°C relative to the current value, followed by a gradual decrease thereafter. That looks like a much bigger problem than sea level rise—but how big? At the same time that the hotter parts of the Earth were becoming unihabitable, the colder parts—Antarctica and currently frozen parts of the Northern Hemisphere—would be becoming habitable. An accurate calculation of the net result would require more expertise than I have and more effort than I am willing to put into the project, but I can at least try a rough back of the envelope estimate.

Warming due to CO2 tends to be greater in cold times and places than in hot, because water vapor is also a greenhouse gas, the warmer it is the more water vapor is in the air, and the more of one greenhouse gas the less the effect of adding another. I do not know how large the difference would be for warming on the scale I am looking at. To simplify my calculations, I will assume that high temperatures in hot areas go up by five degrees, low temperatures in cold areas by fifteen—readers are welcome to recalculate the numbers with other assumptions.

How high do high temperatures have to be to make a place uninhabitable? India is a very hot place and densely populated. Looking at a list of July high temperatures by city, I observe a high of 36°C in Tamil Nadu and Pondicherry. If that represents the upper bound for habitability, another five degrees would make any city currently above 31° uninhabitable. Counting cities, which is less work than looking up regional areas and adding them, I observe that twenty-four out of fifty-two cities are above that, so my very rough estimate is that the projected warming would make almost half of India uninhabitable by a thousand years hence.

Looking at a list of highest temperatures ever recorded by country, the figure for India is 50.6°. Algeria, Iran, Iraq, Kuwait, Mexico, Pakistan and Saudi Arabia equal or exceed that, and a few other countries come close. If I add up the area of India and all countries whose highest temperature is at least as high, I get a total of about 12.7 million square km. To allow for countries a little cooler than India, take it up to 14 million, then divide in half, since my very rough calculation suggests that only about half of India would become intolerably hot.

Very, very rough estimate: A five degree increase in maximum temperatures would make about seven million square km intolerably hot. What would we get in exchange?

Antarctica and Greenland would be ice free, for a total area of about sixteen million square km. How much of that would be warm enough to be habitable I do not know. Siberia is about thirteen million, Canada about ten million. Parts of both are presently habitable, but large parts are not. Similarly for Sweden, Norway, and Finland.

I conclude, from my very rough estimates, that the total habitable area of the Earth would almost certainly go up, not down. I leave to someone more ambitious the task of a more careful and precise calculation. A lot of people would have to move—but a thousand years is a very long time.

Why does all of this matter, given the difficulty of predicting anything a thousand years, even a hundred years, into the future? It matters because it suggests an upper bound to climate catastrophe, at least slow catastrophe. In the worst case, the long term result would be a physical world not strikingly worse for humans, possibly better, than the present world.

If the changes happened over decades there would be enormous human costs. If they took many centuries, probably not.

Why Unlikely Events Are Not Unlikely

A recent FaceBook post starts:

Is it really a coincidence that so many unprecedented weather events are happening this year

with a link to a news story about a "once in 50 years" rain in Japan. It is an argument I frequently see made, explicitly or implicitly. Lots of unlikely things are happening and there must be a reason. When the subject is climate change the unlikely things are mostly about climate.

It looks convincing until you think about it. The world is large. There are lots of different places in it where, if an unusual weather event happens, it is likely to show up in the news. There are at least four categories of unusual weather events that could happen—unusually hot, unusually cold, unusually large amount of rain, unusually small amount of rain—and probably a few others I haven't thought of. A year contains four seasons and twelve months and a record in any of them is newsworthy—a recent news story, for example, claimed that this August was the hottest August in the tropics on the record.

For a very rough estimate of how many chances there are each year for an unlikely event to happen and make the news, I calculate:

100 countries prominent enough + 100 cities prominent enough +10 geographic regions (tropics, poles, North America, ...) + 50 U.S. states = 260

x

12 months + 4 seasons=16
x 

4 kinds of events that would qualify 

=16,640 opportunities each year for an unlikely weather event to occur and be reported.

So we would expect more than 300 once in 50 years events to happen each year and about sixteen one in a thousand events.

My guess is that those number are too low—the story about floods in Japan does not make it clear whether the one in fifty years record is for the whole country or only one region. But they at least show why we should expect lots of unlikely things to happen each year.

If you flip a coin ten times and get ten heads, you should be surprised. If you flip sixteen thousand coins ten times each, you can expect to get ten heads about sixteen times—and should not be surprised when you do.

Another Angle on the Kim Davis Case

One of the less sympathetic features of the case, at least to me, is that her action is entirely symbolic. It does not prevent gay couples from getting married and it only prevented them from getting married in her town for a few days. That makes me suspect, perhaps unfairly, that she is acting not out of religious conviction but either because she likes attention or because she hopes to use the controversy to jump start a political career.

Which gets me wondering how people would feel about her action if it was more than symbolic, if by disobeying a legal rule she disapproves of she could actually keep it from taking effect. It is hard to imagine a version of her story that achieves that, but consider the same issue in a more plausible context:

You are a law enforcement official charged with enforcing the law against marijuana in a state with severe penalties for its violation. You believe marijuana should be legal. You can quietly subvert the application of the law by failing to follow up evidence of marijuana usage, recommending on spurious grounds against prosecution of arrested users, perhaps sending anonymous warnings to targets of investigations by other officers. You expect that you can get away with such actions for many years, since those supervising you are either sympathetic or incompetent. The result will be to save hundreds of people from arrest, conviction, and imprisonment.

Should you do it or should you resign?

For those who think it obvious that you should resign, that obedience to the law takes priority over moral beliefs, consider two real world situations along somewhat similar lines.

1. Jury nullification. If you are on the jury trying someone for a crime of which you believe him guilty but that you do not believe ought to be illegal, should you vote for conviction or acquittal?

2. President Obama's decision not to prosecute a specified subset of illegal immigrants.

Immigration, Welfare and the EU

The strongest argument against free immigration, from the standpoint of supporters of the free market, is that immigrants from poor countries may come not in order to work but in order to take advantage of a rich country's welfare system. Seen from one side it is an argument against free migration, seen from the other an argument against a welfare system. The easier it is for poor people to come to take advantage of welfare, the less attractive redistribution looks to the taxpayers paying for it, hence the less generous the system is likely to be. That may explain why levels of redistribution are generally lower in the U.S., where welfare was traditionally handled at the state level and intrastate migration was free, than in Europe, where welfare was handled at the national level and interstate migration was restricted.

Was. Within the E.U., there is now free migration. That puts pressure on national welfare systems either to reduce the level of transfers or raise redistribution to the supranational level. That pressure was limited as long as all E.U. members were relatively wealthy countries, became greater with the admission of poorer members from eastern Europe.

It is now greater still as the willingness of some European states to accept refugees and treat them generously, combined with conflicts that produce large numbers of actual refugees while making it difficult to distinguish them from voluntary migrants, is creating a flood tide of would-be residents on Europe's southern and eastern borders

One way in which the E.U. might respond is by restricting immigration. That will be difficult when many of the would-be immigrants are fleeing  real dangers, hence natural objects of sympathy. How do you distinguish real refugees from migrants seeking to take advantage of generous transfers (330 € monthly, accommodation, language courses and so on during the six months that it takes Germany to decide whether or not someone qualifies for asylum, according to a comment on a recent post here)? And immigration restriction is made more difficult by the fact that border control is done at the national level. A country with low levels of redistribution can leave its border open in the expectation that most new arrivals will promptly depart for richer fields.

An alternative is to offer asylum on terms sufficiently unattractive so that only those fleeing real dangers will be inclined to take them—no welfare payments for five years, the current Czech policy for non-asylum migrants. That is the immigration policy that I recommended for the U.S., along with open borders, more than forty years ago in the first edition of The Machinery of Freedom.

Either policy might solve the immediate problem but  still leave a situation where rich E.U. nations with generous welfare policies can expect to attract poor people from poorer parts of the E.U.—who, under current law, have the same rights as existing residents. It will be interesting to see whether the result is to shrink the European welfare states or to shift redistribution one level up, converting the E.U. into something a little closer to a United Statues of Europe.

For those in favor of free immigration and opposed to redistribution, the optimum solution, within the E.U. and in the world more generally, is easy. Arguably, the same solution should be optimal for those who support redistribution for egalitarian motives. Open borders plus the abolition of transfer payments might increase inequality in the U.S. or Germany but would surely reduce inequality on a global scale, the poor of India and Egypt, who would benefit, being much poorer than the poor of the U.S. or Germany.

Intuiting the Kim Davis Case

I have to wonder: just how many of those supporting Kentucky clerk Kim Davis’s refusal to issue marriage licenses based on her religious objection to same-sex couples marrying would support a Quaker government official who refused to issue them gun permits based on a religious commitment to pacifism?—Lambda Legal Legal Director Jon Davidson

Davidson's hypothetical works if your objective is to show supporters of Kim Davis how her act looks from the standpoint of those critical of it, although it should include "and refuses to resign," since lots of people, probably including lots of those supporting Kim Davis, would approve of a Quaker who resigned rather than taking an action inconsistent with her religious views. For the reverse project, showing opponents of Kim Davis how the situation looks to supporters:

You are the only trash collector for your town. A recent change in state law has classified homeless people as trash and instructed all local trash collectors to kill homeless people and dispose of their bodies. You were  appointed by an elected official who opposes the new law, so cannot easily be removed. Should you obey the new law, resign your position, or hold the position as long as you can while refusing to kill anyone?

Doing Something

A recent news story has a presidential candidate flirting with the idea of building a wall along the U.S. border—the northern border. His explanation:

Walker has long said that securing U.S. borders, especially the southern border with Mexico, is not only a deterrent to illegal immigration but also a way to ensure that terrorists and international criminals do not enter the country. 

The U.S. hosts about 75 million tourists each year, coming from a wide variety of countries. Does anyone seriously believe that we can filter out from that flood one, or ten, or a thousand bad guys? All a competent terrorist needs is a passport in a name that isn't on a list of people to keep out. I do not know what country in the world is currently the least expensive source of bogus passports, but I would be surprised if the price was high enough to discourage someone supported by ISIS or al Qaeda or ...  .

As in too many other cases, the underlying logic is:

Something must be done.

This is something.

It Could Be an Interesting Election

A recent story claims that Bernie Sanders is planning to drop out of the Democratic race and run as an independent; he has denied it.  Donald Trump has said both that he would and would not consider running as an independent. If one runs and the other does not, that might well throw the election to the other side. The more interesting question is what happens if both run.

Sanders appeals to the left wing of the Democratic party, so the question is how many will vote their ideology at the risk of putting a Republican in the White House.  Trump is a more complicated case, with positions on the  right on some issues,  the center, even the left on others. His appeal, so far as I can tell, is not ideological but personal—he is a more competent demagogue than the other candidates, a point persuasively argued by Scott Adams of Dilbert fame. I would expect him to pull a significant number of votes from the Democrats although more from the Republicans.

If both run, how will the major parties respond? A Sanders campaign would pull Hilary left—arguably already has. A Trump campaign might give the Republican  an incentive to try to match his demagoguery, as some  are doing on the anchor babies issue. Or it might persuade the candidate that Trump's voters are a lost cause—and at least not voting Democratic. That could, to be unreasonably optimistic, improve the chances of Rand Paul or someone similar. And a Republican candidate Democrats only mildly dislike would reduce the incentive for Sanders supporters to vote for Hilary.

Commenters with better worked out ideas of the implications are invited to offer them.

Robert Heinlein, Cell Phones, and Police

Somewhere, Heinlein comments that predicting the direct effects of technological change is relatively easy. What is harder is predicting indirect effects. His example was the automobile. He argued that it had a substantial effect on sexual behavior by giving couples a place to make love out of sight of parents.

I am not sure how convincing that example is, but it occurs to me that we have another and clearer one. Did it occur to anyone, ten or fifteen years ago, that one effect of the development of cell phone technology would be, by providing practically everyone with a pocket video camera, to greatly increase public opposition to police beating people up? 

The closest I can think of is in David Brin's Transparent Society, where he argued that, in a future where everything is subject to surveillance, the transparency ought to go in both directions: The police can watch us, but we can also watch them.  I do not think it occurred to him how we would get there or that the essential change would be not in what you could see but in what you could record and offer for public view.

P.S. Judging by comments, I may have been unfair to Brin, working off my memory of one book, not all of his writing.

Medieval Myth

On an entirely different topic ...  

Given my historical interests, I have long been struck by how inaccurate popular conceptions of the Middle Ages are—summed up in the historically obsolete label of "Dark Ages." My usual example is the myth that medieval food was overspiced to hide the taste of spoiled meat, propagated by people who have never read a medieval recipe, let alone cooked from one, or spent as long as twenty seconds thinking about the consequence for a cook of routinely serving spoiled meat, disguised with expensive spices, to his boss. I also have a pair of accounts of scientific reasoning, one from a Norse saga and one from a 14th century North African.

I have just come across a delightful review of a recent book on the medieval foundations of modern science, written by a reviewer who shares my attitude towards popular confident ignorance on the subject.

Looking for an Honest Man

I believe I have shown that John Cook, lead author of the article commonly cited for the claim that 97% of climate scientists support AGW, has lied in print about his own work. My argument assumed that Cook et. al. 2013 was itself honest, but other people have offered good evidence that it is not.

It is not surprising if there are some dishonest people on one side, or the other, or both of the climate controversy. A more interesting question is whether there are any honest people. Can anyone point at a prominent supporter of action to prevent warming who has publicly rejected Cook et. al. 2013 or its author?

The same question can be asked of the other side. Are there prominent articles criticizing the campaign to prevent warming that are clearly dishonest, clearly enough so that someone with no commitment to either side of the controversy would recognize them as such? If so, have they been publicly rejected by anyone on that side?

Judging Outside Your Expertise

I have just been involved in a lengthy exchange on Facebook over my criticism of the claim that warming on the scale projected by the IPCC for 2100 can be expected to have large net negative consequences. The response I got was that the person I was arguing with was not interested in my arguments. He does not know enough to judge for himself whether the conclusion is true, so prefers to believe what the experts say.

Accepting the views of experts on a question you are not competent to answer for yourself, assuming that you can figure out who they are and what they believe, is often a sensible policy, but one can sometimes do better. Sometimes one can look at arguments and evaluate them not on the basis of the science but of internal evidence, what they themselves say. Here are three examples:

The widely cited 97% figure is based mostly on Cook et. al. 2013, which is webbed. It is often reported as the percentage of climate scientists who believe that humans are the main cause of warming and that warming will have very bad effects. Simply reading the article tells you that the second half is false. The article is about causes of warming and offers no evidence on consequences. Anyone who says it does is either ignorant or dishonest, and other things he says can be evaluated on that basis.

If you read the article carefully you discover that the 97% figure, which is a count of article abstracts not scientists, is the percentage of abstracts which say or imply that humans are *a* cause of warming (“contribute to” in the language of one example). The corresponding figure for humans as the principal cause, which is not given in the article but can be calculated from its webbed data, is 1.6%. That tells you that anyone who reports the 97% figure as the number of articles holding that humans are the main cause of warming is either ignorant or dishonest. One person who has done so, in print, is John Cook, the lead author of the article. John Cook runs skepticalscience.com, which is a major source for arguments for one side of the global warming dispute, so knowing that he is willing to lie in print about his own work is a reason not to believe things on that site without checking them. [My old blog post giving details]

One of the economists who has been active in estimating consequences of warming is William Nordhaus. He is, among other things, the original source for the 2° limit. A few years ago, he published an article in the New York Review of Books attacking a Wall Street Journal piece that argued that climate was not a catastrophic threat that required an immediate response. In it, he gave his figure for the cost of waiting fifty years instead of taking the optimal steps now—$4.1 trillion dollars—and commented that “Wars have been started over smaller sums.” What he did not mention was that that sum, spread out over the rest of the century and the entire world, came to about one twentieth of one percent of world GNP. He was attacking the WSJ authors for an argument which his own research, as he reported it, supported.

In a recent Facebook exchange on the consequences of AGW for agriculture, someone linked to an EPA piece on the subject. Reading it carefully, I noticed that the positive effects of warming and CO2 fertilization were facts, with numbers: “The yields for some crops, like wheat and soybeans, could increase by 30% or more under a doubling of CO₂concentrations. The yields for other crops, such as corn, exhibit a much smaller response (less than 10% increase).” The negative effects were vague and speculative: “some factors may counteract these potential increases in yield. For example, if temperature exceeds a crop's optimal level or if sufficient water and nutrients are not available, yield increases may be reduced or reversed.” The same pattern held through the article.

A careful reader might also notice that the piece referred to the negative effects of extreme weather without any attempt to distinguish between extreme weather that AGW made more likely (hot summers), less likely (cold winters), or would have an uncertain effect on (droughts, floods, hurricanes). It was reasonably clear that the article was designed to make it sound as though the effects of AGW would be negative without offering any good reason to believe it was true. One telling sentence: “Overall, climate change could make it more difficult to grow crops, raise animals, and catch fish in the same ways and same places as we have done in the past.” With most of a century to adjust, it is quite unlikely that farmers will continue to do everything in the same ways and the same places as in the past.

These are three examples of arguments for one side of the climate controversy by a source taken seriously by supporters of that side. Each can be evaluated on internal evidence, what it itself says, without requiring any expert knowledge of the subject. In each case, doing so gives you good reasons not to trust either the source or the conclusion.

Readers may reasonably suspect that I too am biased. But nothing I have said here depends on your trusting me. In each case, you can look at the evidence and evaluate it for yourself. And all of it is evidence provided by the people whose work I am criticizing.

How to Make Economics Fun

I'm currently in Cincinnati, where I gave a talk this evening to an audience of the teachers, high school and college, who grade the AP Econ exam. It was about how to teach economics in ways that will get and hold the attention of students.

It occurred to me that some readers of this blog might be interested.

Dear TSA: Give Up Already

According to multiple news stories, tests of TSA airport inspection by Department of Homeland Security red team agents found that 95% of simulated bombs and weapons were missed by the inspectors. That suggests that the considerable costs and hassles imposed by TSA on passengers over the past thirteen years accomplished almost nothing. The response by both government spokesmen and the media is that they just need to try harder, do a better job. It does not seem to have occurred to anyone that if, after thirteen years, TSA is still unable to keep people from getting bombs and weapons onto airplanes, perhaps it should give up.

That does not mean taking no precautions at all. There are obvious precautions that have nothing to do with inspections, such as reinforced doors to protect the pilot area of an airplane and arming pilots. Terrorists willing to kill other people are easier to find than terrorists willing to kill themselves, so it makes sense to be sure that if the person who checked a bag doesn’t board, the bag comes off. As a protection against hijackers, it might make sense to have armed sky marshalls on many flights or to train and arm members of the flight crew. That would cost considerably less money than the current system and impose no cost in time and hassle on passengers.

Those precautions will not stop someone from blowing up an airplane with himself on it, but, to judge by the results of the red team tests, neither do the current precautions. That no such events have occurred is evidence that few or no attempts are being made.

A defender of the present system could still argue that even if it only stops one or two incidents, it is worth doing, since human life is infinitely valuable. There are two things wrong with that argument. The first is that human life is not infinitely valuable, as shown by the choices humans make. All of us choose to take some risks we could avoid, to drive to visit relatives when we could stay home, to eat something short of the perfect diet, to see the doctor less often than we would if avoiding death was something we regarded as infinitely valuabie.

The second thing wrong with the argument is that the present system also has a cost in life, less visible than a terrorist attack but probably larger than the cost of terrorist attacks prevented by the TSA. The more expensive, in money, time, and hassle airline travel is, the more people choose to drive instead. Driving is a great deal more dangerous per mile than flying, so more people driving means more people dying.

We cannot calculate the number of dead without knowing the size of the shift from flying to driving produced by the TSA, but we can at least get some feel for the order of magnitude. The mortality rate from driving is about one death per 100 million vehicle miles. The mortality rate from flying is very close to zero—one estimate I found was .07 deaths per billion passenger miles. So, roughly speaking, every hundred million passenger miles diverted from flying to driving represents one more highway death.

In February of 2015, passengers on commercial airlines flew 60 billion passenger miles. Assuming the figure is the same for other months, that’s about 700 billion passenger miles a year. If we assume, I think conservatively, that one percent of passenger miles are diverted from flying to driving by TSA hassles, that comes to 7 billion passenger miles or about 70 deaths. Add that up for the thirteen years the TSA has been in operation, and it has killed almost a thousand people. Invisibly.

A Record for LAX

I am currently sitting in LAX en route from San Jose to Cincinnati, where I am giving a talk. I have concluded that LAX holds a record. It is the worst marked airport in the world. It's true that I have not actually been in all of the world's airports so there may be one somewhere that is worse, but I doubt it.

I arrived on Delta, was to leave on United. The Delta terminal had, so far as I could tell, no signs showing what airline flew out of what terminal, no signs showing how to get to terminal 7, which turned out to be where United was, no visible information for any non-Delta flights.

I succeeded in finding my gate by asking people along the way. If I did not speak English—and a lot of people coming through LAX don't—I might still be looking.

LAX is currently under construction, which can explain some problems, but not this. It would be easy enough to make up a signboard showing which airline was at which terminal and put one in every terminal. It would be easy enough to put up signs showing, from each terminal, what direction you went to get to each other terminal. But nobody has bothered, judging at least by the Delta terminal and most of the space between it and United.

A Test for Truth

I have been reading an interesting account of how conscription was ended in the U.S., focusing on my father's role. Near the end of the process, President Nixon established a commission headed by Thomas Gates, a former secretary of defense. Martin Anderson recounts the following exchange between Nixon and Gates: 

But Mr. President, I’m opposed to the whole idea of a volunteer force. You don’t want me as the chairmen.”

“Yes, I do Tom,” the president replied, “that’s exactly why I want you as the chairman. You have experience and integrity. If you change your mind and think we should end the draft, then I’ll know it’s a good idea.”

It struck me as an ingenious solution to the problem faced by someone who needs to make decisions on a variety of questions and does not have the time and energy to research all of them for himself. Instead of trying to appoint a neutral agent to give an unbiased opinion, appoint someone whose honesty and competence you trust who is on what you suspect is probably the wrong side of the question. If you are right, about both him and the question, he will change his mind. If he does not, you may well be wrong.

Assuming that Nixon's explanation of his choice is true, the incident is to his credit.

The commission, set up with people on both sides of the issue, ended by unanimously recommending the abolition of the draft.

Torture and Revealed Preference

One of the latest episodes in the war against ISIS was a raid by U.S forces that killed a leading figure and captured his wife. According to news stories, the intent was to capture Abu Sayyaf, believed to play a major role in financing ISIS via black market sales of oil, for the sake of  valuable information he could provide about ISIS operations. Killing him, while better than nothing, was not the preferred outcome.

That raises an obvious question. Assuming the raiders had been successful, how did they expect to get at information in Abu Sayyaf's head? The most obvious conjecture is by torture—which the U.S. government claims not to engage in. An alternative possibility is by threatening his wife—also not, so far as I know, a tactic U.S. forces admit to using. 

A central principle of economics is revealed preference. What people do provides more reliable information than what they say.

Politicians as People

Politicians are also people, and the question of what sort of people they are is largely separate from the question of what policies they advocate. That struck me recently after I happened to interact casually with two professional politicians, both at a fairly high level. One of them was, loosely speaking, on my side. One was, loosely speaking, on the other side.

The politician I agreed with was a nice enough person, but did not feel like someone it would be fun to spend time arguing with. The reverse was true of the politician I disagreed with. The reason was not that I can't argue with people on my side—I can and frequently do. It was something about the feel of their personalities.

By that standard, my favorite modern politician would probably be Newt Gingrich. I've never met him, but at one point I somehow got on a mailing list for cassette tapes of his talks—by the technology you can guess how long ago it must have been. Pretty obviously, he was bright, opinionated, original, a little crazy. The sort of person I enjoy arguing with.  The overall feel reminded me a little of my friend and ex-colleague the late Gordon Tullock. I am pretty sure that if, by some accident, Gingrich and I were seated next to each other on a long plane flight, neither of us would be bored.

Liberals and Elizabeth Warren

My previous post mentioned the controversy over Elizabeth Warren's claim to be a native American. The facts, as best I can determine them, are that she put herself on the minority law teacher list in her listing in the faculty directory of the American Association of Law Schools, from the mid-eighties until after she received tenure at Harvard, represented herself as native American to both the University of Pennsylvania and Harvard, and was so listed in federal filings by both universities. 

When questioned, Warren explained that she believed, from family tradition, that an ancestor had been Cherokee. When the issue arose during her 2012 senatorial campaign, supporters claimed to have documentary evidence that one of her great-great-great grandmothers had been listed as Cherokee. It eventually turned out that the claim was based on an assertion in a 2006 family newsletter—no actual documentation ever appeared. For an account from a source friendly to Warren, see this Mother Jones article. For a much more detailed account from a critical source, this web page.

Most of the controversy has been over whether Warren's claim was true, but that does not strike me as the interesting question. I not only have no documentary evidence with regard to any of my great-great-great grandmothers or even my great grandmothers, I don't even know their names. And, in any case, what is relevant in evaluating Warren's behavior is not what is true but what she believed.

I will assume, therefor, that Warren really did believe that she had a distant ancestor who was Cherokee. We are still left with the case of a woman who took advantage of preferential hiring policies designed to benefit disadvantaged minorities by claiming to be one in spite of not being a member of a disadvantaged minority in any meaningful sense. 

That is not admirable behavior, but neither is it, in my view, strikingly wicked—people quite often game systems for their own advantage in one way or another. But then, I am not a supporter of affirmative action. One would expect those who are to see it as a modern version of the proverbial offense of stealing pennies from a blind man's cup, diverting to her benefit resources that were supposed to go to other and worse off people. Yet Elizabeth Warren has not only not been ostracized by the liberal community, she has become one of their leading figures.

I can only see two plausible explanations. The less likely one is that most liberals do not really believe in their own proclaimed principles, do not care whether affirmative action policies actually benefit the people they are supposed to benefit. The more likely one is that this is an example of tribal behavior. Warren won back a blue tribe senate seat from a red tribe usurper. That gives her a free pass, the social equivalent of a get out of jail free card. Any evidence against her, however clear, is obviously enemy propaganda to be ignored.

The Trust Problem

In a recent Facebook exchange about Elizabeth Warren's claim to be a native American, someone raised the issue of what news sources one should rely on, comparing Breitbart unfavorably to Mother Jones. In support of that comparison, she cited a web page, NewsTrust, which posts its evaluations of news sources and gives Mother Jones a high rating.

That raises an obvious question that apparently had not occurred to her: What reason do we have to trust NewsTrust? To answer that I looked at their web page and discovered that the single source of information for which it showed the highest rating was Rolling Stone, the magazine responsible for the bogus UVA rape story—not merely a mistake, but a mistake pretty clearly due to irresponsible reporting with an ideological bias. Add to that the fact that the two blogs which they rate on that page are Daily Kos and Think Progress, both well to the left, and I conjecture that their ratings tell me more about which side a source is on than about how reliable it is.

That leaves us with the problem of how to figure out what facts to believe, given that not only news sources but sources of information about news sources are likely to be biased in various ways. In that particular exchange, I had already demonstrated one solution to that problem. The Mother Jones article was introduced to the discussion by me, as evidence against Warren, not for her. Both the politics of the publication and the tone of the story made it clear that any bias would be in Warren's favor. Hence I concluded that any negative evidence it presented was probably true—and cited that evidence in the exchange.

For a detailed discussion of the controversy over the evidence on Warren's ancestry, see this Breitbart piece and its links. Believe it or not as you wish.

Why Good Teachers Get Bad Evaluations

The current Slate Star Codex, my favorite blog, has a link to an account of an interesting piece of research on student evaluations of teachers. It judged the quality of teachers by how well their students did in later courses,  compared the result to student evaluations of teaching quality, and found that the two anti-correlated. On average, good teachers get bad ratings, bad teachers get good ratings. For details, follow the link.

It's a single study, I have not read the original paper, and the result might be wrong. But it is interesting to think about reasons why it might well be right.

The most obvious one is that many students don't like to work hard. A professor who does not assign much homework or reading and grades easily might get better ratings, from many although not all students, than one with the opposite pattern. My daughter, as a student at Oberlin, was struck by the fact that most of the other students in a class were happy when, for some reason, it didn't meet. The same pattern—study seen as a cost, not a benefit—might well apply here.

There is a second and less obvious possible reason. Correct ideas are frequently hard. Easy ideas are frequently wrong. My standard example is from popular discussions of foreign trade issues. Most of them take for granted a view of the economics of trade, the view implicit in terms such as "unfavorable balance of trade," that  economists refer to as the theory of absolute advantage. That particular view of the subject has been obsolete for about two hundred years. But while the theory of absolute advantage does not make sense if you think about it carefully, it is considerably easier to understand than the theory of comparative advantage, which does. That is why the former was worked out first and why it has had such a successful postmortem career.

A professor who insists on telling the truth, on explaining hard ideas correctly, may well come across as a worse teacher than one who fudges, offers a simplified and less correct version. Half the students of the former end up believing that they do not entirely understand the subject being taught—and they are right. Almost all the students of the latter end up sure they understand it—and wrong.