Book Reviews

Expert Political Judgment

Posted by Peter on September 22, 2006
Posted in: Book Reviews, Politics. Tagged: .

Book review: Expert Political Judgment: How Good Is It? How Can We Know? by Philip E. Tetlock
This book is a rather dry description of good research into the forecasting abilities of people who are regarded as political experts. It is unusually fair and unbiased.
His most important finding about what distinguishes the worst from the not-so-bad is that those on the hedgehog end of Isaiah Berlin’s spectrum (who derive predictions from a single grand vision) are wrong more often than those near the fox end (who use many different ideas). He convinced me that that finding is approximately right, but leaves me with questions.
Does the correlation persist at the fox end of the spectrum, or do the most fox-like subjects show some diminished accuracy?
How do we reconcile his evidence that humans with more complex thinking do better than simplistic humans, but simple autoregressive models beat all humans? That seems to suggest there’s something imperfect in using the hedgehog-fox spectrum. Maybe a better spectrum would use evidence on how much data influences their worldviews?
Another interesting finding is that optimists tend to be more accurate than pessimists. I’d like to know how broad a set of domains this applies to. It certainly doesn’t apply to predicting software shipment dates. Does it apply mainly to domains where experts depend on media attention?
To what extent can different ways of selecting experts change the results? Tetlock probably chose subjects that resemble those who most people regard as experts, but there must be ways of selecting experts which produce better forecasts. It seems unlikely they can match prediction markets, but there are situations where we probably can’t avoid relying on experts.
He doesn’t document his results as thoroughly as I would like (even though he’s thorough enough to be tedious in places):
I can’t find his definition of extremists. Is it those who predict the most change from the status quo? Or the farthest from the average forecast?
His description of how he measured the hedgehog-fox spectrum has a good deal of quantitative evidence, but not quite enough for me check where I would be on that spectrum.
How does he produce a numerical timeseries for his autoregressive models? It’s not hard to guess for inflation, but for the end of apartheid I’m rather uncertain.
Here’s one quote that says a lot about his results:

Beyond a stark minimum, subject matter expertise in world politics translates less into forecasting accuracy than it does into overconfidence

Evolution’s Rainbow

Posted by Peter on September 20, 2006
Posted in: Book Reviews, Politics, The Human Mind. Tagged: , .

Book review: Evolution’s Rainbow: Diversity, Gender, and Sexuality in Nature and People by Joan Roughgarden
This book provides some good descriptions of sexual and gender diversity in nature and in a variety of human cultures, and makes a number of valid criticisms of biases against diversity in the scientific community and in society at large.
Many of her attempts to criticize sexual selection theory are plausible criticisms of beliefs that don’t have much connection to sexual selection theory (e.g. the belief that all sexually reproducing organisms fall into one of two gender stereotypes).
Her more direct attacks on the theory amount to claiming that “almost all diversity is good” and ignoring the arguments of sexual selection theorists who describe traits that appear to indicate reduced evolutionary fitness (see Geoffrey Miller’s book The Mating Mind). She practically defines genetic defects out of existence. She tries to imply that biologists agree on her criteria for a “genetic defect”, but her criteria require that a “trait be deleterious under all conditions” (I suspect most biologists would say “average” instead of “all”), and that it reduce fitness by at least 5 percent.
Her “alternative” theory, social selection, may have some value as a supplement to sexual selection theory, but I see no sign that it explains enough to replace sexual selection theory.
She sometimes talks as if she were trying to explain the evolution of homosexuality, but when doing so she is referring to bisexuality, and doesn’t attempt to explain why an animal would be exclusively homosexual.
Her obsession with discrediting sexual selection comes from an exaggerated fear that the theory implies that most diversity is bad. This misrepresents sexual selection theory (which only says that some diversity represents a mix of traits with different fitnesses). It’s also a symptom of her desire to treat natural as almost a synonym for good (she seems willing to hate diversity if it’s created via genetic engineering).
She tries to imply that a number of traits (e.g. transsexualism) are more common than would be the case if they significantly reduced reproductive fitness, but her reasoning seems to depend on the assumption that those traits can only be caused by one possible mutation. But if there are multiple places in the genome where a mutation could produce the same trait, there’s no obvious limit to how common a low-fitness trait could be.
Her policy recommendations are of very mixed quality. She wants the FDA to regulate surgical and behavioral therapies the way it regulates drugs, and claims that would stop doctors from “curing” nondiseases such as gender dysphoria. But she doesn’t explain why she expects the FDA to be more tolerant of diversity than doctors. Instead, why not let the patient decide as much as possible whether to consider something a disease?

Stumbling on Happiness

Posted by Peter on September 12, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , , , .

This book is a colorful explanation of why we are less successful at finding happiness than we expect. It shows many similarities between mistakes we make in foreseeing how happy we will be and mistakes we make in perceiving the present or remembering the past. That makes it easy to see that those errors are natural results of shortcuts our minds take to minimize the amount of data that our imagination needs to process (e.g. filling in our imagination with guesses as our mind does with the blind spot in our eye).
One of the most important types of biases is what he calls presentism (a term he borrows from historians and extends to deal with forecasting). When we imagine the past or future, our minds often employ mental mechanisms that were originally adapted to perceive the present, and we retain biases to give more weight to immediate perceptions than to what we imagine. That leads to mistakes such as letting our opinions of how much food we should buy be overly influenced by how hungry we are now, or Wilbur Wright’s claim in 1901 that “Man will not fly for 50 years.”
This is more than just a book about happiness. It gives me a broad understanding of human biases that I hope to apply to other areas (e.g. it has given me some clues about how I might improve my approach to stock market speculation).
But it’s more likely that the book’s style will make you happy than that the knowledge in it will cause you to use the best evidence available (i.e. observations of what makes others happy) when choosing actions to make yourself happy. Instead, you will probably continue to overestimate your ability to predict what will make you happy and overestimate the uniqueness that you think makes the experience of others irrelevant to your own pursuit of happiness.
I highly recommend the book.
Some drawbacks:
His analysis of memetic pressures that cause false beliefs about happiness to propagate is unconvincing. He seems to want a very simple theory, but I doubt the result is powerful enough to explain the extent of the myths. A full explanation would probably require the same kind of detailed analysis of biases that the rest of the book contains.
He leaves the impression that he thinks he’s explained most of the problems with achieving happiness, when he probably hasn’t done that (it’s unlikely any single book could).
He presents lots of experimental results, but he doesn’t present the kind of evidence needed to prove that presentism is a consistent problem across a wide range of domains.
He fails to indicate how well he follows his own advice. For instance, does he have any evidence that writing a book like this makes the author happy?

Undercover Economist

Posted by Peter on September 3, 2006
Posted in: Book Reviews, Economics. Tagged: , .

Book review: The Undercover Economist: Exposing Why the Rich Are Rich, the Poor Are Poor–and Why You Can Never Buy a Decent Used Car! by Tim Harford
This book does an excellent job of describing economics in a way that laymen can understand, although experts won’t find much that is new in it.
Harford’s description of price discrimination is the best I’ve seen, and the first to describe how to tell the extent to which an instance of price discrimination has good effects (the extent to which it expands the number of sales).
His arguments that globalization reduces pollution are impressive for most types of pollution, but for carbon dioxide emissions I’m very disappointed. He hopes that energy use has peaked in the richest countries because he’s failed to imagine what will cause enough increased demand to offset increases in efficiency. For those of modest imagination, I suggest thinking about more realistic virtual reality (I want my Holodeck), personal robots, and increased air conditioning due to people moving to bigger houses in warmer climates. For those with more imagination, add in spacecraft and utility fog.
Some small complaints:
He refers to Howard Schultz as the owner of Starbucks, but he only owns about 2 percent of Starbucks’ stock.
His comment that Amazon stock price dropped below its IPO price fails to adjust for stock splits – a share bought at $18 in 1997 would have become 12 shares worth $8 each in the summer of 2001.
His claim that “Google is the living proof that moving first counts for nothing on the Internet” is a big exaggeration. It’s quite possible that Google success was primarily due to being the first to reach some key threshold of quality, and that many small competitors have matched its quality without taking measurable business away from it.

Time

Posted by Peter on August 24, 2006
Posted in: Book Reviews, Science and Technology. Tagged: .

Book Review: The Labyrinth of Time: Introducing the Universe by Michael Lockwood
This book provides a great overview of the more interesting parts of modern physics, with some emphasis on time and the philosophy of time.
It is less clearly focused on time than the cover suggests. If you want a deep and narrow focus on time, Huw Price’s book Time’s Arrow is more appropriate and provocative.
Labyrinth of Time explains many things better than other physics books do.
For instance, the standard description of the twin paradox suggests that acceleration is responsible for the differences in how each twin ages. Lockwood refutes that with a nifty diagram of a cylindrical space-time where unaccelerated twins age differently on world-lines of different lengths.
The book provides good explanations of why the alleged paradoxes of time travel aren’t sufficient to imply that time travel is impossible.
Lockwood does a relatively good job of arguing in favor of the Everett (many world) interpretation of quantum mechanics, but that section requires enough experience with the subject that many laymen will have trouble following it.
The speculations he reports about how time might mean before the Planck time are really strange.

Kanzi

Posted by Peter on July 25, 2006
Posted in: Book Reviews, Science and Technology, The Human Mind.

Book Review: Kanzi: The Ape at the Brink of the Human Mind by Sue Savage-Rumbaugh
This book makes plausible claims that some bonobos have learned to handle language in a way that is approximately as sophisticated as that of a two year old human. But their anecdotal evidence is somewhat hard to evaluate, and they didn’t quite convince me that they were careful enough to rule out the possibility that their biases caused them to overestimate the sophistication of Kanzi’s understanding.
The book is a bit long-winded about research that Savage-Rumbaugh did before working with Kanzi, and I was a bit disappointed that the book didn’t provide more of the anecdote about Kanzi that made the book worth reading. But those anecdotes convinced me that much more is going on than some authors such as Pinker had led me to believe. I still hope for better evidence that will help clarify how much bonobos can understand. But that will be hard, and I don’t know how it should be done.

Last Well Person

Posted by Peter on June 28, 2006
Posted in: Book Reviews, Health. Tagged: , .

Book Review: The Last Well Person: How to Stay Well Despite the Health-care System by Nortin M. Hadler
There appears to be a large discrepancy between how effective most people think modern medical practices are and the evidence that experts have presented suggesting that it does very little to extend life. This book gives the impression of describing a pattern of ineffective or harmful practices that might be offsetting the benefits of the practices that are known to work. But there are enough flaws in his argument that I can’t decide how much of his conclusions I should accept.
He starts by saying he’s a Popperian, but often acts like he’s following some other, more dogmatic, philosophy. I’m particularly annoyed at his certain feelings of inevitability that we will die by about age 85:

I am aware of no data to support the premise that we can alter the date of death. … When high-functioning octogenarians decline, it is because their time is approaching.

He starts by making a plausible claim that many people get cardiovascular surgery when there’s no evidence that it will benefit them (and is likely to create some risks).
But starting in the next chapter it becomes easy to find flaws in his arguments. He raises some plausible doubts about the evidence for statins, but then tries to imply that if the imperfect evidence that’s available shows that less than 2% of people who are prescribed statins will benefit, then we should doubt that those people ought to take statins.
He presents evidence that prostate cancer treatments save fewer lives than is commonly thought. It appears that sometimes the treatment merely changes the cause of death to something else. Yet he concludes that the treatment is useless, when the data he presents indicate nontrivial benefits. He hints that the evidence doesn’t meet the usual standard of statistical significance, but feels comfortable concluding (without even saying how close it is to being statistically significant) that the lack of proof is strong evidence of ineffectiveness.
He has a somewhat interesting proposal that the final phase of drug testing be done by the FDA rather than by drug companies. If the FDA were run by angels, that would solve a number of problems with the existing regulatory incentives, but with an FDA run by humans it would replace them with new problems. For instance, the choice of which drugs to test is something that only a few special interest voters (i.e. mainly those working for large drug companies) would understand, so their interests would be likely to influence those choices to the benefit of those companies.

Unusual Bodies

Posted by Peter on June 21, 2006
Posted in: Book Reviews, Health, Miscellaneous.

Book Review: One of Us : Conjoined Twins and the Future of Normal by Alice Domurat Dreger
This book raises questions about peoples’ reactions to conjoined twins that may have important implications for many other unusual traits. It eloquently questions common assumptions about the desire to seem normal. It has led me to wonder about the extent to which healthcare is used to make people more normal at the cost of making them less healthy.
The book presents strong evidence that conjoined twins who remain conjoined are at least as well off as those who are separated, and some evidence that separations reduce the twins’ life expectancy, possibly by a significant amount.
Remarkably, of the twins who remained conjoined to adulthood, only one pair requested separation (they didn’t survive it), and among those whose refused separation are a number whose twin had just died (which meant that separation appeared to offer the only chance for the remaining twin to survive).
This doesn’t mean conjoined twins are better off that way (those who have been separated seem equally satisfied with their status), but it strongly suggests that decisions to perform separations are motivated by something other than concern over the twins wellbeing. And it suggests that people who claim things like “The proposed operation would give these children’s bodies the integrity that nature denied them” are imposing their values on others in ways which would be considered unacceptable if the victims had a little political power.
The book reports a fair number of statements by doctors (and occasionally parents) which suggest they consider a normal appearance worth risking health to achieve. The book also theorizes that having a normal child is an important enough part of parents’ identity to override their interest in their children’s’ wellbeing. The book also reports some indications that surgeons are biased toward surgery for unusual problems by the fame if can bring them.
Unfortunately, there isn’t as much evidence as there ought to be about the health effects of separations. The book claims (plausibly, but without supporting references), that “most medicine is not yet evidence-based”, with most surgical decisions being based on storytelling rather than careful studies.
The book raises some important questions about cases where doctors think the only way to save one twin is to kill the other. The author points out some strong similarities between the medical killing that is done in some of these cases and a hypothetical case where a heart is taken from a live singleton (i.e. not conjoined) donor to save another (which all would agree is wrong). One difference that she fails to consider is that if you consider the heart property, it looks like jointly owned property in one case and individually owned property in the other, and we should expect some differences to result from that (although doctors may still be more willing to kill one twin than that perspective would justify).
One interesting example that the book provides of medicalizing a difference is the attempt to get doctors to recognize Drapetomania, a “disease” which causes slaves to run away.
How widespread is the practice of impairing health to make people more normal? Surgeries on intersex children probably create modest health risks. Commonly used medicines to deal with ordinary colds suppress annoying symptoms that are tools the body uses to fight the disease, and tend to make the disease last longer (see the book Why We Get Sick : The New Science of Darwinian Medicine by Randolph Nesse). A child with 3 arms makes doctors want to chop it off, presumably at some risk.
Are these part of a wider pattern that would help explain why increased healthcare spending doesn’t seem to make us healthier?
On a loosely related note, I just ran across an unsettling complaint that Prozac seems to help too many people:

“There’s nobody nonsyndromal. You can give Prozac to anyone you want.”

Which is anathema to what medical science is supposed to be about. “We try to convince people there’s some specificity to what we do,” says Millman. “But this is embarrassing.”

Is this an indication that people don’t want drugs to do anything other than treat abnormal conditions (i.e. that they consider it wrong to improve on normal conditions)? Or does it reflect concern that there will be less demand for doctors’ skills if no diagnosis is relevant to the decision to use it? (This seems less likely given that they can still play a role in monitoring side effects).

I was inspired to read this book by a brief comment from Robin Zebrowski at the recent Human Enhancement Conference.

1491

Posted by Peter on June 14, 2006
Posted in: Book Reviews, Freedom, Life, the Universe, and Everything. Tagged: , , .

Book Review: 1491 : New Revelations of the Americas Before Columbus
by Charles C. Mann
This book does a good job of discrediting several myths about the nature New World civilizations before Europeans arrived. It implies that significant parts of the book Guns, Germs, and Steel are wrong (in ways that Diamond should have avoided by consulting experts) – Indians were quite capable of repelling Europeans when their advantage consisted of guns and steel. After smallpox spread across the Americas (faster than Europeans), guns and steel were largely superfluous advantages.
The book presents evidence (alas, not enough to be conclusive) that most of the land in the Americas had been altered by civilizations that were much more sophisticated and varied than is commonly realized, and the myth that Indians were primitive savages is largely due to people mistaking the disease-ravaged remnants that the typical European colonist encountered for the pre-European norm.
The book also provides a few bits of evidence against historical determinism by pointing out how differently some aspects of civilization developed in the two worlds. For instance, the New World seems to have been first to get the concept of zero, but only used wheels for toys, and valued metals for their malleability rather than strength.
One very intriguing report is that the Haudenosaunee (Iroquois) Confederation society was freer and more egalitarian than European society, and that this caused a number of Europeans to prefer Haudenosaunee society, but no Indians in that region preferred European society. It’s unclear how strong the evidence is for these somewhat controversial claims. I guess I ought to track down the books he references for this subject.
The book also describes the Inka empire as socialist, without any markets, but I’m disappointed at how little the books says about that (e.g. how broad a definition of market is he using?).
The main shortcomings of this book are the numerous anecdotes that add little to our understanding of Indian civilizations.

Operation Yao Ming

Posted by Peter on May 27, 2006
Posted in: Book Reviews, China.

Book Review: Operation Yao Ming: The Chinese Sports Empire, American Big Business, and the Making of an NBA Superstar by Brook Larmer
This book is a very readable biography of Yao Ming.
But I had been led to hope that it would inform me about China’s future. I’m disappointed at how little it tells me about that subject. It provides some moderately interesting tidbits of information about China’s recent history, but the book doesn’t attempt to provide the kind of understanding of China that would tell us whether those tidbits are a glimpse of a past that is being abandoned or whether they contain useful indications of China’s future.