Tuesday, November 29, 2011

Probably Linda (Continued)

The Linda Problem, which I discussed last time, is an illustration of how ordinary people do not engage in "right thinking." We are told the story of an imaginary woman, Linda, who was heavily into social justice and anti discrimination and you are asked which is more probable, that she is a bank teller or that she is a bank teller and a feminist. The correct answer is, in the world of probability theory, she is a bank teller. You are supposed to realize that adding the information she is a feminist reduces the probability, because there is a small chance that those characteristics which we associate with someone who might become a feminist does not guarantee she is a feminist. She might have been brought up in the Bible belt and while she shares some sympathies which are common among feminists, she does not embrace all the rest.

On the other hand, this whole problem hinges on your embracing the conventions of probability as it is taught in schools. What you are doing when you fail to think right, is you are going with "street knowledge" as opposed to what you've been taught in class, usually a class at some elite university or prep school. You have been schooled to think right.

But suppose we change the meaning of the word "probability" to the meaning it might have in the real world or say, the world of espionage. Suppose, for example, we are told the story of Linda, who has been tracked from her home in Russia to a training school in the elite Russian intelligence agency known to train sleeper agents who come to the United States, get ordinary jobs and ply their trade. Now I ask you the question: What is the greater probability A/ She is bank teller B/ She is a bank teller who is a Russian spy?

Now, of course, same rules apply by Dr. K's theory: She is a bank teller is the correct answer. It is possible she is not a Russian spy. The rest of the evidence is circumstantial and it is unproved she is working for the Russian spy agency which ran to the school, which got her her visa and provided her money, car and home. There is a small, however small chance, she is not a spy. She may have rejected all that training and just enjoys life in America as a bank teller. The chances may be small she is not a spy, but the chances are not zero.

On the other hand, if you are watching this on TV, or on the jury, while you understand more evidence is needed and you understand the chances are not 100% she is a spy, you know the greater probability is she is a bank teller (which is irrelevant, given the totality of the information you have been given) and a spy than the probability she is simply a bank teller.

If we had a jury of engineers, math majors and Ivy League graduates she might be set free. If we had a Baltimore jury, she's a spy.

Who is thinking more right, now?

Monday, November 28, 2011

The Linda Problem


Reading a review of Daniel Kahneman's Thinking, Fast and Slow, I ran across this problem which resonated with me: You are asked a simple question about Linda, who you are told is an imaginary woman who as a student was deeply moved by concerns about discrimination and social justice. You are asked which is more probable: A/ Linda is a bank teller B/Linda is a bank teller who is active in the feminist movement.
Of course, the answer is A, because adding the detail can only lower the probability. Any engineer or math major will choose A.
I would have taken B, knowing the answer is A. This is why I could never score 800 on my SAT exams. I would have answered B because: 1/ It is the more interesting answer. 2/ It indicates I can infer something about Linda from the extra information about her, even if what I infer may be wrong, it provides a more interesting working hypothesis. 3/ It shows I was thinking about Linda and wanted to know more about her.

It is also an attempt to spit in the eye of the obvious.

I also got questions wrong like: Does England have a Fourth of July? Now, of course, I knew, England uses the same calendar we do, but when you capitalize the Fourth, then you are talking about our American holiday celebrating what England might not be expected to celebrate, i.e., our independence from England. Answering "no" indicates I have thought beyond the literal to the implied. Would England be celebrating this holiday? Some uneducated American might think they are setting off fire works in England because the Fourth of July must be a holiday everywhere, because this goof ball has never thought past the fireworks to what the holiday is all about. I wanted to show I knew what the holiday celebrates, so I answered no, knowing it is, in a literal sense, wrong.

It's thinking like this which has gotten me into academic trouble my whole life.

People who can force themselves to "Just answer the question," i.e. to think in a certain way, will score high on their SAT's and go to Harvard.

A high school classmate of mine in senior advance placement English completed an assignment, "Trace the use of 'roads' through the
Tale of Two Cities," by writing down every time the word "road" appeared in the book. (And this was before computers with word search.) She had a five hundred page list of, "Road appears on page 1," and so forth. And she started to go through this as I (and several of my classmates) sat there, mouths on our chests, astonished. After about three minutes of her cataloguing the appearance of "road" I finally said, "Uh, Martha, I think the point of the question is Dickens uses "road" as an image. He's saying we all travel different roads, with different and divergent paths through life." Martha stared at me, uncomprehending. She scored high on her SAT's and she went to Harvard. Heaven only knows what became of her.

Toward the end of my third year in medical school, a dean pulled me aside and said, "You know you have got honors in every rotation third year, including Neurology, and you were the first student to get honors in Neurology in five years. But you were just below the middle of your class, 51 out of 100 at the end of the second year. What got into you?"

I said, "I didn't change. What changed were the people who were asking the questions."

He had no clue what I was talking about. But the questions on the tests during the first year were of the "Trace the use of Roads" and they meant, literally, recite the page numbers. In third year, you had to infer and use all of the information given you to form meaning.

A different sort of mind excelled in the first two years' setting. My roommate, who used to sit motionless with his microbiology book in his lap, just reading and memorizing, did superlatively his first two years, while I made outlines and tried to fit all the detail into meaningful categories: There must be a reason they separate gram positive bacteria from gram negative bacteria. Perhaps they behave differently when they cause infections. But no, in the second year microbiology course the differences in the diseases caused by the two groups were of no concern. All they wanted you to know was which bug stains gram negative, which gram positive. It was memory without meaning.

It was: Memorize this--NYSE, DJA, WSJ, and so on. So many meaningless letter combinations. I was unable to do this, and I would have to say, "Okay, think of some meaning for these letters. Think of financial pages: New York Stock Exchange. NYSE. Get it? Now you can remember.

When we got to the wards, suddenly I was able to use the information I had learned the first two years. For my room mate, none of it helped. He was barely able to keep his head above water. Nothing on the wards made sense. He had no outlines in his head. He went from a top twenty student to below 50. But he was a star when all he had to do was "answer the question." Don't try to attach a meaning to your answer.

Later, when we applied for internships, the wise men who reviewed our applications said, "Well, Bob is a really intelligent guy. His first two years show that. He just had no personality. Third year grades are all about charm and personality. It's the first two years which tell you how bright medical students are."

I would beg to differ. The questions in the first two years, multiple choice, the answer is right there in front of you; answer A or B, did not allow for inference, attaching meaning. The probability is greatest Linda is a bank teller, not that she is a bank teller with some specific characteristic of feminism. She might, after all have been an impassioned rejector of discrimination and social injustice, but there's a slim chance a woman who was that sort of student is not a feminist now. Strictly speaking, the answer is A.

The person who answers "A" is not any smarter or dumber than the person who picks "B."

The problem is not with either the person or the answer; the problem is with the guy who judges one better, more correct, than the other.

And, as far as I can tell, too many people who have been in a position to judge other people have not understood the limitations of their own thinking. They have seized upon easy formulae because it's easier for them to cling to their beliefs.

These are the same sorts who read US News and World Reports and believe Harvard is a better college than Stanford this year, but last year believed just the reverse, because the US News and World Reports gave the opposite answer last year. Something must have changed over the year. There couldn't be anything wrong with the method of the US News and World Reports.

I'll look forward to reading Thinking, Fast and Slow, because I have been told it explores "systematic errors in thinking of normal people." But if the basis for this analysis is the Linda problem, I may well be concluding the error is not in the thinking of normal people but in the thinking of those narrow minded judges. People answer not the question asked, sometimes, but the more interesting aspect raised by the question, the part that interests them, not the part that interests the questioner. Many people care nothing about probability, especially when the probability is so obvious, so they ignore that and go to the "better" answer.

It reminds me of that wonderful line in Roger Rabbit where Eddie, the detective, explodes at Roger for an answer which was clearly wrong and he asks how Roger could have made such a
obviously wrong statement when the truth was right in front of him and Roger stammers, rather astonished Eddie could not see why he answered that way: "Because," Roger says, "It was funnier that way."

For Roger, it was important to choose the answer he liked better, not the answer the questioner liked better.

I get this every day, when I take a medical history from a patient. I ask a specific question and the patient answers a slightly different question, a question he is more interested in, or a question he knows the answer to rather than the question I asked which he does not recall the answer to.

This is not because he is stupid. It is because he cannot see the underlying reason for my question, because he doesn't have my training. It's up to me to point out how he has answered a different question, and I need the answer to the one I'm interested in. I don't tell him he gets no points for his answer. I just ask the same question again, maybe a different way. Often, it turns out he didn't know the answer.

"What hour of day do you take this drug?" He cannot remember when he takes that drug. All he knows is he takes his drugs when his wife tells him to. So he tells me about how he feels after he takes his bedtime drugs, how he has to get out of bed an hour later and pee after he takes his bedtime drugs. "But do you know whether you take this drug I'm asking you about at bedtime?"


"Hell, doc," I just take those little pills out of that plastic box with the morning, noon, dinner, bedtime compartments. I don't know which drugs are in what compartment."

Okay, now we are getting somewhere. He did not know the answer I'm looking for. But he had his reasons for answering the way he did.

Saturday, November 26, 2011

Priests of Their Own Desire




Christopher Leinberger is a senior fellow at the Brookings Institution and a professor of practice in urban and regional planning at the University of Michigan.

Now there is a set of credentials which lies somewhere between impressive and intimidating.

Given that on your letterhead, you can write an article which the New York Times which will run above the fold on the op ed page, with a little art sketch adorning it.

Professor, senior fellow, Leinberger has analyzed some statistics, which makes his invocations unassailable. He looked at the Zillow real estate database, so he has some big numbers, and big numbers can never be wrong, or misinterpreted.

And what did he learn? He learned the collapse of the mortgage system was not caused by the avarice and shenanigans of brokers who used bogus, immoral, wildly doomed-to-fail mortgages to back stocks which were sold as can't fail because the most reliable, most vetted, surest bet things in the world are mortgages, which people will always pay because their homes are the things they value most in life--home and hearth.

Nope, the reason the mortgage system collapsed is the rise in appeal of the inner city, places which mean people do not need cars, can walk out of their townhouses and shop and walk to the theater, the museum the shopping they like.

So outer suburbs are bad. McMansions, with too many rooms, too much space, to much land between houses which tend to isolate rather than foster communities, are unattractive, nasty places to live and will inevitably be abandoned and decay, like Tara from Gone with the Wind, which is actually the name of a McMansion development in Potomac, Maryland, the fantasy upon which those tracks of large homes were built.

Now, I love New York City, personally. I loved the neighborhoods, where you walk along the sidewalks and everything is at street level: newspaper stores, laundry, grocery stores. You can buy shoes, get them repaired, and everything within walking distance. Or, you can jump down into a subway. If I could afford it, I'd still love to live in New York City or a place with all those characteristics.

But I would not try to argue that my personal preferences are confirmed as the way things should be for my countrymen based on my "analysis," of "data."

Actually, there are things about living in New York City and any like urban environment I found difficult: There was, eventually, a claustrophic feeling. I didn't spend much time in my apartment, but eventually, I started paging through L.L. Bean catalogues for images of country life. Shopping was restricted to what you could carry, groceries limited to what would fit in a roller crate. Buying furniture or any bulky items was a problem, but you don't do that all that often.

There is much to recommend urban life, and clearly New York City is better for the environment than living in suburbs, with the damage done by cars, the energy required to heat and cool large homes, the use of water and pesticides for lawns and gardens.

But there are trade offs, and not everyone, especially parents with small children, are willing to make them. City children have to be taught to stop running at the corner so they cannot be kidnapped when they turn out of sight.

I would love to see more city options emerge. I'd love to see Portsmouth, New Hampshire become a small Upper West Side, and Portland another Brooklyn. Personally, I'd love to see that. But I very much doubt I can read the minds of my countrymen based on the Zillow real estate database, and I doubt Professor Leinberger can either.

You see this sort of "analysis" and "thinking" done by most politicians and many "commentators." They begin with their own likes and dislikes and find "data" and numbers, the bigger the better to "prove" what they like is the best for everyone.

I am not a Brookings Institution fellow, but I got to believe that thousands of local bankers consumed with ambition, burning with avarice, had something to do with the housing mortgage crash, as they pushed loans on people who could not afford them, telling those gullible, eager to believe folks that yes, this part of the American dream can be theirs; it's all so simple, just move into this dream house. I'm a banker for Pete's sake. Would I lie to you?

I don't know, but I find that scenario easier to believe than the scenario painted by Professor Leinberger, that of wealthy one percenters driving through Potomac, Maryland and McLean, Virginia, shaking their heads a the sight of those stone mason walls, those sweeping driveways and saying to themselves--nope, I'd rather live in Logan Circle, in downtown Washington, DC, with its horrific, dysfunctional city government, its constantly changing neighborhoods, which only a few years ago were so crime ridden and violent nobody wanted to walk there, much less live there, which were so forbidding restaurants could not survive there.

It's true more and more of Washington, DC has gentrified, but for how long is anyone's guess. Cities may be drawing more affluent people back in as they "downsize" once their children have grown up and moved away, but, actually, I would not be at all surprised to learn most boomers are staying put in their empty homes, because they cannot sell them for anything close to what they would need to sell them for, in order to pay for pricey urban homes. And the boomers, especially the older ones, often find any change difficult, so the suburbs may be senescent and senescing, but I bet they are not going to wither into ghost towns, as Professor Leinberger hopes.

The sad fact is, many inner cities are still decaying--just look at Detroit--and parts of Washington, DC have never recovered from the riots of 1968. I wish it weren't true. I wish those lovely brownstones in Bedford Styvestant, Brooklyn were being brought back to life; I wish the Grand Concourse in the Bronx was being rejuvenated. But no, despite the wishes of urban planners, urban blight persists. Baltimore sinks deeper and until government and policy and basic institutions like schools, police, media and banks and industrial base can actually find adequate people to make rational decisions, that city will never come back.

There may be ghost towns of unsold suburban homes in Arizona or in Ireland, but the homes of aging boomers will remain occupied until they die, I would bet. And I suspect my bet, based on no data is just as likely to be correct, as Dr. Leinberger's guess, who based his explanations on his holy scripture, the Zillow data.

This is the sort of "analysis" you hear from Rush Limbaugh every day. It's more sophisticated, and the numbers are examined with greater care, but it amounts to the same thing in the end: The expert, the opinionator, arrives at his conclusion not because a dispassionate observation leads him to question, hmm, why do you suppose sales around Logan Circle were better than sales in Potomac the last year? It's got to be people are finally coming around to the value of inner cities, and at this point in the lives of our aging population, the inner cities serve their needs better. They have finally awakened to the wisdom of what I've believed and preached all these years.

Or not. Actually, not.

Wednesday, November 9, 2011

I Would Rather Be Phil Sheridan's Widow




Phillip Sheridan played a monumental part in winning the Civil War. Battles, campaigns depended on his leadership. It was no accident he was in the room with Grant, to witness Lee's surrender at Appomattox Court House.




His wife, who was 24 years younger, was an Army brat, grew up around soldiers, the daughter of an officer.




She had been thought a great beauty and after he died, she was young and still beautiful and everyone from close friends to newspaper reporters asked her when she might marry again. She said, famously, "I would rather be Phillip Sheridan's widow than any living man's wife."




She died in 1917, during World War One, in a house just blocks from Sheridan Circle in Washington, DC, Phillip Sheridan's widow, a wizened little woman, grown old, alone.




Perhaps, she was simply a child of the nineteenth century, a woman who clung to those romantic notions of love and marriage we, in the 21st century, associate with times long gone. Perhaps there was something there we might today call psychopathology. A woman who would rather live with the dead than with the living. A sort of fulfilled Mrs. Haversham, not living in jilted bitterness, but in the past, nevertheless.


Or maybe, she was just saying, "I had a man with whom none other can compare. Why should I live with someone for mere companionship?"




I don't believe for a moment men or women of the 19th century really believed, in private, the myths of finding a soul mate who God intended for them to marry, or any of the socially useful delusions peddled at marriage ceremonies.




I suspect, but cannot know, this woman grew up in a culture which prepared her to admire certain characteristics in men: Courage, perseverance, tenacity, leadership, intelligence and honesty. Whatever his faults, Sheridan had all this in spades, and she could see it, recognize it and compare him to other men and say, "This man is the best man I have ever known, or likely ever will know."




Sheridan burned and pillaged farms throughout the Shenandoah Valley, and he took the skills and lessons he learned during the Civil War to Texas, after the Civil War and analyzed the problem white settlers were having with the Comanches. Just as the Shenandoah had been the breadbasket for Lee's army, the buffalo were the breadbasket for the Comanche Plains Indians. Eliminate the buffalo, he said, and you will bring the Comanches to their knees. So he arranged for the wholesale slaughter of the great buffalo herds and applied his burnt earth strategy to the war with the Comanche and won. "The only good Indians I saw," he said, "Were dead Indians."




So, he was not, by 20th century, multicultural, ecological standards, an example of enlightened thinking.




He was brutally honest.




His wife could see that.




She was no Jackie Kennedy.




I wonder how many 21st century women think this way. If any glimpse into the souls or minds of women can be gleaned from the New York Times Style section wedding "announcements" with the self serving stories of how women met their mates, and what attracted them, then one would have to conclude, women today, for the most part, do not look for men they admire. They look for men with good earning potential, or for men who might make good fathers while they pursue their own careers, or for any number of things, but not for a man who is a hero in any sense of the word.




I'm sure there are exceptions.


I suppose there are women who see men in the work place who are heroes, by today's standards. Those women may marry "for love," in the sense Mrs. Sheridan married. And with time and domesticity those heroes look less heroic. Apparently Phillip Sheridan did not look less heroic with time.


If it were a good thing for women to marry heroes, as a policy, that would leave a lot of unmarried women, because there are few heroes, in the Phil Sheridan sense, in these times. Even in his times.


But it does make one wonder about how marriage and what it means has changed through the years.


But whatever love is in the 21st century, I don't think it's based on what Mrs. Sheridan saw, on what moved her.