David D. Friedman's Blog, page 13

A Real Life Catch-22

I recently received a phone call from Blue Cross for my son William. The call was fully automated—recordings and voice recognition. It asked if I was William. When I replied that I was not, it asked me to take a message for him. The message was that he was to call a specific phone number.
I passed the information on to William, who is a student at the University of Chicago. He called the number from his cell phone—and was informed, I assume again by a robot responder, that he had to respond from the phone number that the original call had gone to—my home number in San Jose.
He reported the result to me. I called the number. The robot asked me if I was William. I replied that I was not. It asked if I was representing him. I replied that I was. It told me to tell him to call the number and hung up on me.
I called the general Blue Cross number, eventually got through to a human being, and described the elegantly impossible situation that I had encountered. He put me on hold, checked the situation, then informed me that the call was for a survey and he could and would remove William from the list of people being surveyed. I pointed out that the same problem would occur for anyone else being surveyed who was not living at the location of his home phone number and suggested that Blue Cross might want to alter the way they did their survey. My guess, from his response, is that it won't happen.

Successful Dieting: Report from a Sample Size of One

I have been somewhat overweight for a long time. In recent months, for the first time I can remember, I have succeeded in losing quite a lot of weight—something over twenty pounds—by dieting. The methods that turned out to work for me may work for some other people, although surely not all, so I thought it was worth describing them.
The diet started when my wife was out of town for over a month taking care of her mother, who had broken her arm and needed assistance. The reason that made it easier was not the difference between her cooking and mine—I am an adequate cook. It was the fact that eating is in part a social activity. Her absence made it much easier for me to skip meals. 
I have the good fortune to possess a metabolism that is not bothered by skipping meals; I can fast until dinner time without serious discomfort or other negative consequences. So one part of my diet, then and thereafter, was to limit myself to one meal a day, with only a little nibbling at other times. Usually the meal was dinner. Occasionally there was a lunchtime talk on campus with lunch provided, in which case I would make that my one meal and only have a light snack in the evening.
Another part of the diet was finding low calorie food I liked. That largely consisted of fruit salads, using fat-free cottage cheese, yogurt, or mayonnaise, all three of which taste pretty good and are quite low in calories. For snacks, the best solution was kimchee, the highly spiced Korean pickled cabbage which, I concluded, has the highest ratio of taste to calories of any food known to man. I also indulged in an occasional pummelo, the ancestor of the grapefruit, a fruit I had recently discovered and found to be quite tasty.
The final factor was feedback. I got a digital scale, put it in the bathroom, and weighed myself several times a day. Partly that was curiosity, seeing how my weight varied over the course of a day. The range was surprisingly large, typically including a drop of three pounds or so between immediately after dinner and the next morning. But the continual feedback also encouraged me to push my weight lower and warned me when a temporary deviation was letting it come back up.
The most discouraging part of the process occurred after I had reached my initial target, tried to return to something closer to my usual eating pattern of a light lunch plus a substantial dinner, and found that my weight was going back up. So I went back on the diet. I have yet to determine what pattern I need to follow in order to maintain a roughly constant weight, or whether the answer will change once my body has adjusted to its new level.
Recently I was invited to a black tie event, the first such I can  remember attending. In my closet was a very good suit that my parents bought me decades ago for such purposes, and that I had not worn—could not wear—for a very long time. The pants still did not fit, but they were a lot closer to fitting than they had been a few months earlier; I wore a less fancy suit to the event instead. 
I figure that when I can get into those pants, my diet will be done.

More on Nordhaus and Global Warming

In a blog post a while back, I pointed out that William Nordhaus's work on the economics of global warming demonstrated a serious problem with policy arguments based on externalities—the risk, in dealing with something as uncertain as costs and benefits over the next century, that the calculation of externalities will be biased in the direction that produces the result the person doing the calculation wants. Nordhaus included, as an essential part of his argument, an estimate of the expected cost from low probability/high cost outcomes of permitting global warming but made no attempt to include the cost of equivalent outcomes from preventing it—although there is no strong reason to assume that the current global climate is optimal, and so that any change will produce costs but not benefits.
Robert Murphy has webbed a detailed response to a recent Op-Ed by  Nordhaus on global warming, dealing with a variety of other issues. Among his points:
1. Climate models have, on average, overpredicted warming, suggesting that a better estimate would be about 2/3 the current predictions of such models.
2. The paper which Nordhaus cites as supporting the claim that CO2 is a pollutant actually provides evidence that net externalities are positive over a temperature range representing about the next fifty or sixty years of predicted rise, and go negative only after that.
3. Nordhaus's own work finds that the optimal policy to reduce global warming, coordinated among all nations of the world, produces net benefits, but that some proposed policies, including one proposed by Gore, produce much larger net costs. 
One point Murphy did not make but that is worth noting is that the benefits of climate control, on Nordhaus's own figures, are not very large. The optimal policy—for obvious reasons not likely to occur—is calculated to produce a net benefit of about three trillion dollars. That sounds like a lot of money—until one recognizes that it is spread over the entire world and about ninety years. That makes the annual benefit of the ideal policy about 33 billion dollar a year—roughly one percent of the current U.S. federal budget or one tenth of a percent of current world income. 
Which suggests that, with a less ideal and more realistic policy, net costs are likely to be larger than net benefits.

A Mass-Market Electric Car?

I recently came across a news story on the Coda, a new electric car, and noticed that one of the few dealers was within a few miles of my house. Yesterday I stopped by, explained that I wasn't really in the market but was curious, and was given a chance to drive it.
The Coda claims to be a five passenger car, but looked a little cramped for four adults. Its general feel was respectable but not luxurious. What is interesting about it is the price—MSRP of $37,250. State and federal subsidies are supposed to total about ten thousand dollars, bringing the cost to the buyer down to not much more than a comparable conventional sedan.
Claimed range on a single charge is up to 125 miles, time to fully recharge on a 240 outlet about six hours. Allowing for a reasonable safety margin, that makes it good for a trip of forty to fifty miles each way or a commute of up to twice that distance with  a charging station at the other end. My guess is that that would make it an adequate replacement for something like half of U.S. autos—a car for someone who didn't take long trips, or the second car of a family that did.
If the figures I was given were correct, that 120 miles costs about four dollars worth of electricity, a third to a quarter the cost of gas for a similar car with a conventional engine. For a car driven ten thousand miles a year, that is a savings of about a thousand dollars a year, not enough to justify the list price of the car but sufficient to make it a reasonably attractive buy with current subsidies. 
The current subsidies may not—hopefully will not—continue indefinitely, especially if the number of cars being sold becomes large. But I was told that nearly half the cost is for the batteries, so if battery technology continues to improve the price without subsidy might fall to somewhere in the twenty to thirty thousand dollar range in a few years. And if improvements include an increase in energy density, the range could become adequate for all save long trips.
Which is interesting. The Tesla is a snazzy looking car, but definitely a luxury vehicle. The Coda, if it performs as advertised and no unexpected problems show up, could be a serious competitor in the mass market in not very long.

Confession Under Torture: The Visigothic Solution

Quite a lot of legal systems have used torture to try to force defendants and/or witnesses to tell the truth. Moral problems aside, the obvious problem is that an innocent defendant may confess, or a witness give the testimony he thinks the interrogator wants, to avoid the torture.
Obvious not only to us but to them. The legal literature of Imperial China, where torture of both witnesses and defendants was legal, contains accounts of cases where a clever official figured out that a confession under torture was bogus and successfully identified the real criminal.

Much of what we know about the Athenian legal system comes from orations written by professional orators to be spoken by plaintiffs or defendants. They include two orations, written by the same orator for different cases, one of which argues that testimony under torture (of slaves) is entirely reliable, one of which gives the obvious argument for why it is not—in each case, of course, supporting his client's position.
I recently came across an ingenious, if imperfect, solution to the problem in what is apparently the oldest surviving Germanic law code—the Visigothic Forum Judicum. Alaric accuses Beremud of murder. There is not enough evidence to convict Beremud, so he is tortured to make him confess. Under the code:

 "The judge shall take the precaution to compel the accuser to specifically describe the alleged offence, in writing; and after he has done so, and presented it privately to the judge, the torture shall proceed; and if the confession of him who is subjected to the torture should correspond with the terms of the accusation, his guilt shall be considered to be established. But if the accusation should allege one thing, and the confession of the person tortured the opposite, the accuser must undergo the penalty hereinbefore provided; because persons often accuse themselves of crime while being tortured.

If Beremud is innocent, he won't know the details of the offense—where and when the victim was killed, with what weapon, what wounds were inflicted. However much he wants to stop the pain, he can't confess what he does not know. This assumes, of course, that an innocent defendant will not know the details of the crime. The code dealt with that problem:

But if the accuser, before he has secretly given the written accusation to the judge as aforesaid, should, either in his own proper person, or by anyone else, inform the party of what he is accused, then it shall not be lawful for the judge to subject the latter to torture, because the alleged offence has become publicly known."

There is at least one  problem with this solution to the problem of false confessions. A guilty defendant, knowing the law, may confess under torture and deliberately get the details wrong. My conjecture is that that problem was dealt with by having the interrogator  keep up the torture until either the defendant confessed with the right details or the interrogator was convinced that he could not. I suspect that most of us, having had the good fortune not to have been subjected to torture, overestimate how easy is to hold out when saying the right words will end the present pain.
It may occur to some readers that a variant of the Visigothic solution survives in modern practice. Police officers are not supposed to torture defendants, but they are allowed to interrogate them, and interrogation sometimes leads to confessions—which may make one suspect that it comes closer to torture than it is supposed to. One way of checking whether the confession is for real is to see whether it contains details that an innocent defendant would not know.
Of course, this depends on the honesty of the officers doing the interrogation—they can, and for all I know sometimes do, subvert the process by feeding the defendant information that they have and he, if innocent, does not.

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P.S. A talk I just heard on the problem of jailhouse snitches points out a different modern version of the problem—the "confession" by a defendant that may have been invented by the person it was supposedly confessed to, a fellow criminal eager to testify in exchange for lenient treatment in his own case. Here again, one test of truth is whether the confession contains details that the real criminal would know and an innocent defendant, or the fellow criminal who claims to have heard the confession, would not. Here again, the problem is that the snitch may have been fed that information by the police or prosecution, or obtained it himself in some other way.

One further problem, in that case, is that the snitch may be, in some cases turned out to have been, the real criminal, eager to convict someone else for his crime. And well informed about the details.

Wanted: A Better Search String

I routinely use Google to look for people talking about me, in part out of curiosity, in part because, like other people, I like to feel important, and in part because they may be saying things to which I want to reply. 
In the old days, it was pretty easy—most of the hits were people actually saying something about me. As the Internet has grown, the search has become more complicated, both because there are more other David Friedmans online—including another law professor who blogs and an economic journalist—and because a lot of the hits I get are simply web pages that have a link to this blog.
I expect some of my readers know more than I do about the construction of search strings. Ideally, I want one that will not produce a hit for a page whose only mention of my name is a link to this blog. I would also like one that will not return multiple hits for the same reference appearing in multiple places, something that also often happens. Is there a way of doing that? Alternatively, is there a better search engine for the purpose than Google?

Truth, Falsity, and Jobless Numbers

I recently came across a web page with the following claim:

Given the difficulty of estimating economic data it is common practice for government agencies to announce a preliminary number subject to later revision. Under the law of averages, estimates should balance out between being higher or lower than later revisions. Amazingly, though, the Obama Department of Labor's preliminary estimates of new jobless claims have been lower than later revisions in 56 of the last 57 weeks.  

The claim was followed by what purported to be a quote from Labor Secretary Hilda Solis. 

"We feel it is better to err on the side of optimism," she said. "The preliminary estimate is widely reported. The subsequent revisions are rarely noticed. By adding a bit of sheen to the preliminary estimate we feel we are helping to boost morale. We believe that good morale is an important building block for positive change.""Making the economy look better will make people feel better," Solis went on. "If people feel better they are more likely to support the policies of the Administration, which we feel is crucial if we are to be given the opportunity to continue on the path laid out by the President for another four years."

My immediate reaction was suspicion—the quote sounded too much like what a critic of the President would imagine his labor secretary saying and quite unlike what an administration official would actually say. I put a comment on the web page to that effect, adding that I didn't have an opinion on whether the initial fact was true.
Further investigation found the quote only on pages hostile to the administration, and no source other than another such page. On the other hand, the fact, initial underestimates for 56 of the past 57 weeks, is from the Wall Street Journal and so presumably true.
I conclude that the labor department has indeed been deliberately misrepresenting the evidence—erring in the same direction 56 times out of 57 is not something that has any significant probability of happening by chance. The obvious explanation is  the one given in the purported quote. But I am quite confident that the labor secretary didn't actually say what the quote asserts she said, at least not in public.

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P.S. A commenter points out that the "quote" from the labor secretary actually originated as part of a longer piece, obviously intended as satire.

Pretty good satire, too.

Fossil Law

The talk I described in my previous post dealt with a problem at the intersection of federal tax law and state marriage law. Thinking about it, it occurred to me that the problem was in part due to the existence of fossil law—legal rules that once made sense but no longer did.
Let me start with a science fictional example. At present, it is a safe assumption that most twelve year olds know less and are less mature than most adults. Given that, it makes sense to base legal rules such as who gets to vote or who is able to sign a binding contract on chronological age—despite the fact that some twelve year olds, such as one who was a baby sitter for our daughter when she was little, are more mature than some adults. The alternative would be considerably more complicated rules, requiring a larger element of discretion by whomever had the job of interpreting them.
Suppose the situation changes—genetic engineering, mind drugs, radically improved educational techniques, or the like, result in most twelve year olds being mentally and emotionally the equivalent of adults. The old laws might remain, for a while, despite the disappearance of the facts that had justified them.
For a real world example, consider the question of who counts as a child's parents. The old rule was that the mother was the woman from whose body the child was born, the father that woman's husband if she had been married and cohabiting with him at the time the child was conceived. The first part made obvious sense, the second served to eliminate legal controversies at a time when there was usually no better way of establishing paternity.
Neither rule makes sense any longer. The woman from whose body a child is born may be a host mother carrying another woman's egg. Paternity testing makes it possible to prove, beyond any reasonable doubt, that a particular man is or is not the child's father. The law has to some degree altered to take account of those changes, as in the California case of the child with five parents; the court ignored the literal implication of existing law and concluded that the couple with parental rights and responsibilities was the couple who had arranged for the child to come into existence, not the egg donor, sperm donor, or host mother. Adapting rules of child support to the existence of paternity testing has proved harder, probably because the relevant authorities are more concerned with finding some man to hold responsible for child support than with finding the right man.
Coming back to where I started, consider the same issue in the context of the tax treatment of married couples. Back when the federal income tax was created, and later when it was modified to permit joint returns, the typical married couple consisted of two people, one of whom was the principal money earner, the other responsible for running the household and bearing and rearing the couple's childen. Most married couples fit that pattern, and most couples that fit that pattern were married. The legal and social sanctions against unmarried sex, still more unmarried motherhood, were strong enough to discourage, for most couples, the option of separating the legal status of marriage from the reality of the relationship.
Even then, the map did not perfectly fit the territory. There were married couples where both parties were employed, there were households with the marital division of labor (minus the child bearing part) whose members were not married to each other—a parent and his or her adult child living together, two siblings, or some similar pairing. And there were some couples living in sin—married in fact but not in law, although if they were in a state that recognized common law marriage that might be only a temporary situation.  
But the standard model of marriage worked well enough so that it may have made sense to base tax rules concerning marriage on the assumption that all marriages fit that pattern, and everything that fit that pattern was a marriage. And unless the rules provided a really large penalty or bonus to being married, for most people that decision would be determined by other and more important considerations, so the IRS did not have to worry too much about tax rules driving people into or out of marriage.
None of that is true any longer. That suggests that, however the tax law chooses to deal with households in which individuals share, in some form, income and the work of household production, the defining rule should probably not hinge on whether the household members are legally married to each other. Which, among other things, would eliminate the problems associated with same sex couples that were the subject of my colleague's talk.
For a very different example of the  problem, consider the crime of statutory rape, sex with an underage partner. In legal theory, criminal liability requires intent. In practice, statutory rape is a strict liability crime. Even if the offender did not know the age of his partner, even if the partner fraudulently misrepresented her age, perhaps with the assistance of a borrowed driver's license, the adult partner is potentially liable for a serious felony. That, at least, is my understanding of the law—readers who are better informed are welcome to correct it.
Sixty years ago, before the pill and the sexual revolution that it helped to produce, that did not represent a serious problem from the standpoint of the legal authorities. It was true that it meant that someone engaged in non-marital sex with a relative stranger was at risk of committing a serious crime without knowledge or intent. But non-marital sex, especially with relative strangers, was not something that the relevant authorities had any objection to discouraging.
For an example of that attitude a little earlier, consider the explanation of the "usefulness" requirement in patent law offered by a prominent 19th century jurist. He explained that there was no reason not to grant a patent on something of no use to anyone, since nobody would have any reason to infringe it. What the requirement was intended to prevent was the patenting of inventions that were positively pernicious—such as a device to facilitate private assassination—Judge Story apparently anticipated James Bond, the CIA, and targeted drone strikes—or debauchery. 
Modern patent law imposes a more stringent interpretation of the usefulness requirement, but it would be hard to argue that devices to facilitate debauchery—viagra, say, or the pill itself, or online software for locating sex partners—are pernicious, hence unpatentable. While modern norms do not regard casual sex as the ideal, they do take it largely for granted.

In a society where meeting a stranger in a singles bar and ending up in bed with her is not merely legal behavior but acceptable behavior, there are serious problems with a legal rule that can lead from a one night stand to several years in prison without requiring either knowledge or intent. Whether those problems will eventually lead to changes in the law I do not know. But they probably should.
Readers are welcome to offer other examples of fossil laws, and suggestions of how they might best be changed.

The Supply Function for Marriage: A Natural Experiment

Today I attended an interesting talk by a colleague, on the tax consequences of the clash between state and federal law. Her particular interest was a current problem—same sex couples who were recognized as married, or the equivalent for purposes of taxation, by the state they lived in, but not by the IRS. Her description of the historical background to the problem, the past interaction between state law and federal taxation, suggested to me an interesting but unrelated idea—the possibility of using a past legal anomaly as a natural experiment to determine the supply elasticity of marriage.
Federal tax law, now and in the past, bases its definition of what income belongs to which taxpayer on state law. In a community property state, back before the invention of the joint return, half of a couple's income was attributed to the husband, half to the wife. In states that did not recognize community property, on the other hand, the husband was taxed on his income, the wife on hers. 
When tax rates become significantly graduated in response to the need to pay for WWI, that meant that  high income single-earner couples paid substantially lower taxes in community property states. One possible response was for such couples to move to community property states, and apparently some did. Another would be for a high income bachelor living in a community property state to get married, thus shifting half his income to his wife's lower rate. 
Which get us to my natural experiment. The situation I have described lasted for twenty years or so, easily long enough for individuals to observe it and respond. Was one response an increase in the fraction of high income men living in community property states who were married, relative to the fraction in non-community property states? If so, the size of the effect would give us a measure of the elasticity of supply of marriage—how the number of people who get married responds to financial incentives to do so.
It should be a good project for a PhD thesis, assuming the necessary data—marriage rates by income group and by state—exist.

Alcohol, Warming, and Professionally Correct Speech

Recently, while driving, I listened to a satellite radio program called "Doctor Radio," talk radio by doctors.
In the course of the program, the question of alcohol and health came up. All of the participants agreed that evidence showed that a moderate level of alcohol consumption, something like one beer a day for a woman, one or two for a man, or the equivalent in other drinks, was good for you, better than no alcohol at all. All of them also agreed that they would not advise their patients to act on that evidence.
They did not offer an adequate explanation  for the apparent inconsistency. There was mention of the fact that a higher level of consumption was dangerous, in particular likely to lead to auto accidents, and that there were problems with prescribing something that depended on the exact dosage—but distinguishing one beer a day from three is not  a difficult problem, even for those who are not doctors. 
My conjecture was that the real explanation was the reluctance of doctors to appear to be on the wrong side. Everyone knew that alcohol was a bad thing, a source of auto accidents and various medical (and other) problems. By giving a truthful account of the medical evidence, the doctors on the program might appear to be pro-alcohol, when all good people were  anti. Hence they had to qualify their conclusion as a purely theoretical matter, not something that would actually affect what they told their patients. Think of it as a different version of PC—Professionally Correct speech.
It reminded me of a similar pattern in a different context. From time to time, I see a news story on some piece of scientific research that somewhat weakens the case for taking strong action against global warming—for instance, work suggesting that, while the IPCC projections were correct about the expected magnitude of warming, they overstated its uncertainty, and hence the risk of some outcome much above the center of the reported distribution of results.
I believe that every time I have seen such a report, it was accompanied by a quote from the researchers to the effect that global warming was a serious problem and their work should not be taken as a reason to be less worried about it. They almost certainly believed the first half of that. On the other hand, their work was a reason to be less worried, if not a reason to stop worrying. 
Good people are on the side that believes that warming is happening, is anthropogenic, and is a serious problem that needs to be dealt with immediately. Bad people deny one or more of those claims. If that is what all the people who matter to you, in particular the fellow members of your profession, believe, and you are so unfortunate as to produce results that strengthen the bad people's case, it is prudent to make it clear that you are still on the side of the angels. Just as, if you are so unfortunate as to be an honest doctor aware of the evidence in favor of alcohol, it is prudent to make it clear that have not transferred your allegiance to demon rum.