Global Catastrophic Risks conference

Posted by Peter on November 20, 2008
Posted in: Molecular Assemblers (Advanced Nanotech), Science and Technology. Tagged: , , , .

The Global Catastrophic Risks conference last Friday was a mix of good and bad talks.
By far the most provocative was Josh‘s talk about “the Weather Machine”. This would consist of small (under 1 cm) balloons made of material a few atoms thick (i.e. needed nanotechnology that won’t be available for a couple of decades) filled with hydrogen and having a mirror in the equatorial plane. They would have enough communications and orientation control to be individually pointed wherever the entity in charge of them wants. They would float 20 miles above the earth’s surface and form a nearly continuous layer surrounding the planet.
This machine would have a few orders of magnitude more power over atmospheric temperatures to compensate for the warming caused by greenhouse gasses this century, although it would only be a partial solution to the waste heat farther in the future that Freitas worries about in his discussion of the global hypsithermal limit.
The military implications make me wish it won’t be possible to make it as powerful as Josh claims. If 10 percent of the mirrors target one location, it would be difficult for anyone in the target area to survive. I suspect defensive mirrors would be of some use, but there would still be serious heating of the atmosphere near the mirrors. Josh claims that it could be designed with a deadman switch that would cause a snowball earth effect if the entity in charge were destroyed, but it’s not obvious why the balloons couldn’t be destroyed in that scenario. Later in the weekend Chris Hibbert raised concerns about how secure it would be against unauthorized people hacking into it, and I wasn’t reassured by Josh’s answer.

James Hughes gave a talk advocating world government. I was disappointed with his inability to imagine that that would result in power becoming too centralized. Nick Bostrom’s discussions of this subject are much more thoughtful.

Alan Goldstein gave a talk about the A-Prize and defining a concept called the carbon barrier to distinguish biological from non-biological life. Josh pointed out that as stated all life fit Goldstein’s definition of biological (since any information can be encoded in DNA). Goldstein modified his definition to avoid that, and then other people mentioned reports such as this which imply that humans don’t fall within Goldstein’s definition of biological due to inheritance of information through means other than DNA. Goldstein seemed unable to understand that objection.

Intrade versus FiveThirtyEight

Posted by Peter on November 6, 2008
Posted in: Idea Futures, U.S. Politics. Tagged: , .

A number of people have compared the final forecasts for the election (e.g. this), but I’m more interested in longer term forecasting, so I’m comparing the state-by-state predictions of Intrade and FiveThirtyEight on the dates for which I saved FiveThirtyEight data a month or more before the election.

Here is a table of states where Intrade disagreed with FiveThirtyEight on one of the first four dates for which I saved FiveThirtyEight data or where they were both wrong on July 24. The numbers are probability of a Democrat winning the state’s electoral votes, with the Intrade forecast first and the FiveThirtyEight forecast second.

State 2008-07-24 2008-08-22 2008-09-14 2008-10-01
CO 71/68 60/53 54.5/46 67.5/84
FL 42/29 34.5/28 30/14 55.2/70
IN 38/26 34.1/15 20/11 38/51
MO 50/26 32.9/13 22.1/11 42.5/48
NC 30/22 25/21 14/7 51/50
NV 51.2/49 49/45 44.9/32 55/66
OH 65/53 50/38 40/29 53.5/68
VA 60.5/50 52.3/36 42/22 59/79

On July 24, both sites predicted Florida, Indiana, and North Carolina wrong. FiveThirtyEight got Indiana right on Oct 1 when Intrade was still wrong, but Intrade got North Carolina right on that date (just barely) while FiveThirtyEight rated it a toss-up.
Intrade got Nevada right on July 24 (just barely) while FiveThirtyEight got it wrong (just barely).
For Virginia, Intrade was right in July and August while FiveThirtyEight was undecided and then wrong.
FiveThirtyEight got Colorado wrong on September 14, but Intrade didn’t.
FiveThirtyEight got Ohio wrong on August 22, while Intrade got it right.
Intrade rated Missouri a toss-up on July 24, while FiveThirtyEight got it right.

On September 14, FiveThirtyEight was fooled by McCain’s post convention bounce by a larger margin than Intrade, but by Oct 1 FiveThirtyEight was more confident about correcting those errors.
For states that were not closely contested, there were numerous examples where Intrade prices where closer to 50 than FiveThirtyEight. It’s likely that this represents long-shot bias on Intrade.

In sum, Intrade made slightly better forecasts for the closely contested states through at least mid September, but after that FiveThirtyEight was at least as good and more decisive. Except for Intrade’s Missouri forecast on July 24, the errors seem largely due to underestimating the effects of economic problems – errors which were also widespread in most forecasts for other things affected by the recession.

In the senate races, I didn’t save FiveThirtyEight forecasts from before November 1. It looks like both Intrade and FiveThirtyEight made similar errors on the Alaska and Minnesota races.
[Update on 2009-01-13: contrary to initial reports, they apparently got the Alaska and Minnesota races right, although there’s still some doubt about Minnesota.]

On the other hand, Intrade had been fairly consistently (but not confidently) saying since early July that California’s Proposition 8 (banning same-sex marriage) would be defeated. Pollsters as a group did a somewhat better job there by issuing conflicting reports.

Automated Market Maker Changes

Posted by Peter on November 1, 2008
Posted in: Idea Futures. Tagged: , .

I’ve made a change to the software which should fix the bug uncovered last weekend.
I’ve restored about half of the liquidity I was providing before last weekend. I believe I can continue to provide the current level of liquidity for at least a few more months unless prices change more than I currently anticipate. I may readjust the amount of liquidity provided in a month or two to increase the chances that I can continue to provide a moderate amount of liquidity until all contracts expire without adding more money to the account.
I’m not making new software public now. I anticipate doing so before the end of November.

Stock Market Crashes

Posted by Peter on November 1, 2008
Posted in: Investing. Tagged: .

Many people seem to be reacting to the recent stock market crash the way they wish they had to the 1987 crash, and a smaller number are comparing it to 1929.
The unusual resemblance to the crash of 1937 makes me expect something in between those two scenarios.

  • The 1937 crash was caused in part by a sudden increase in caution by banks after the Fed significantly increased their reserve requirement. Banks played no interesting role in the 1929 or 1987 crashes.
  • The 1929 and 1987 crashes followed stock market peaks in August, versus March and the prior October for the 1937 and 2008 crashes.
  • The 1937 and 2008 crashes both came eight years after one of history’s largest stock market bubbles.
  • The 1929 and 1987 crashes followed an increase in the discount rate to 6 percent. The 1937 and 2008 crashes followed decreases in the discount rate to 1 and 2.25 percent.

All four crashes happened mainly in October and their behavior in that month provides little reason for distinguishing them.
If the 1937 crash is a good model for what to expect in our near future, many investors who are currently following the lesson they learned from the 1987 crash will discover in early 2009 that the unexpectedly severe recession casts doubt on the belief that crashes create good buying opportunities. How many of them will stick to their buy and hold commitment then (when I expect it will be a good idea)?
When the extent of the recession becomes disturbing, remember Brad DeLong’s perspective:

Is 2008 Our 1929? No. It is not. The most important reason it is not is that Bernanke and Paulson are both focused like laser beams on not making the same mistakes as were made in 1929….
They want to make their own, original, mistakes..

(HT James Hamilton).

Automated Market Maker Problems

Posted by Peter on October 26, 2008
Posted in: Idea Futures. Tagged: .

Last night an Intrade trader found and exploited a bug in my Automated Market Maker, manipulating DEM.PRES-TROOPS.IRAQ until Intrade rejected one of the market maker’s orders for lack of credit and the software shut down.
The bug involves handling of partial executions of orders, and doesn’t appear to be easily fixable (what happened looks nearly identical to the scenarios I had analyzed and thought I had guarded against).
For the moment, I’ve reduced the market maker’s order size to one contract, which will prevent further exploitation but provide much less liquidity.
I will try to fix the bug sometime in November and increase the order size (on the contracts that don’t get expired at election time) by as much as I can without adding more money to the market maker’s account. I will also analyze the information provided by the markets shortly after the election.

None of the above for president

Posted by Peter on October 21, 2008
Posted in: U.S. Politics.

I had been half-heartedly planning the past few months to vote for Libertarian presidential candidate Bob Barr. I had previously considered voting for Obama when it looked like he would make an important difference in the Iraq war, but it now looks like the Iraqi government will persuade the U.S. to leave soon enough for that difference not to matter. If I lived in a swing state and the election was close, I might persuade myself that Obama’s personality and intelligence make him more qualified, but my track record for evaluating politicians that way is sufficiently unimpressive that I ought to be uncertain whether I’ve been fooled by his eloquence.
Voting Libertarian is normally the best way to encourage whoever wins to adopt a better policy, but this time it’s unclear whether that would send the message “I want more unprincipled opportunists”. Barr’s past support for the war on some drugs and his current mixed opinions on that subject are damaging the Libertarian party’s reputation.
The final straw that has convinced me not to vote for him is in this New Yorker piece:

For Barr, the terrorist attacks of September 11, 2001, and the subsequent expansion of executive power under President Bush, were a political turning point. “I went through Reagan National after 9/11, and saw guardsmen with automatic weapons,” he told me. “It dawned on me that we’ve entered a whole new world. It may have made other passengers feel more secure, but it made me feel dramatically less free.”

An NRA director saying the presence of armed men is a threat to freedom? There’s no shortage of dishonest pretenses of security that directly interfere with the average passenger. I haven’t heard any indication that armed guardsmen in airports do anything to innocent people. I saw more armed soldiers in the Zurich airport in the late 1980s than I saw in U.S. airports, and I’m fairly sure they didn’t erode Swiss freedom.
This is sufficiently bizarre as to suggest he can’t keep track of which ideology he believes today.
Not to mention this older report where he seems to specifically say Reagan National should have armed guardsmen.

Seasteading08

Posted by Peter on October 14, 2008
Posted in: Freedom. Tagged: , .

The first Seasteading conference went rather well. It got a good turnout of intelligent people, in spite of being on a weekday (they didn’t plan far enough ahead to find a good weekend spot).
I was somewhat disappointed by the time spent on the basic motivations behind seasteading (do people come to this kind of conference without understanding the motivations?), and I wanted to focus more on a serious analysis of how close the business plans are to being a good investment.
One interesting idea that was briefly mentioned is unmanned farms, herded by small robotic boats. If you’re willing to lose farms to an occasional storm, that drastically cuts costs. But when I imagine the cheapest possible farms, it seems the plants would get significant salt spray, which drastically limits the types of crops which will thrive.
The most interesting subject was Ephemerisle. Before the conference I had been wondering whether it would be interesting enough that I would want to attend. The conference convinced me that it will attract the kind of people I like, and that there will be some interesting technical challenges. Since my very rusty knowledge of sailing seems to leave me better informed than most seasteaders about some of those challenges, I will want to provide some help with the planning. It’s still too poorly thought out for me to feel confident that it will be done safely, but it can probably be planned well enough to be safe under most conditions (and hopefully people will be prepared to cancel it if unusual winds make it look unsafe).
The location seems very uncertain, and will have some important impacts on the risks. During the conference, the tentative plan seemed to be a few miles of the southern California coast, but afterward I got some indications that the plan had changed to the San Francisco bay, which would be a good deal easier but which would do less to promote any long-term vision.

Misbehavior of Markets

Posted by Peter on October 5, 2008
Posted in: Book Reviews, Investing.

Book review: The Misbehavior of Markets: A Fractal View of Risk, Ruin & Reward by Benoit Mandelbrot.
Mandelbrot describes some problems with financial models that are designed to provide approximations of things that can’t be perfectly modeled. He pretends that pointing out the dangers of relying too much on imperfect approximations shows some brilliant insight. But mostly he’s just translating ideas that are understood by many experts into language that can be understood by laymen who are unlikely to get much value out of studying those ideas.
His list of “ten heresies” is arrogantly misnamed. Sure, there are some prestigious people whose overconfidence in financial models leads them to beliefs that are different from his “heresies”, but those “heresies” are closer to orthodoxies than they are to heresies.
His denial of the equity premium puzzle is fairly heretical, but his argument there is fairly cryptic, and relies on suspicious and poorly specified claims about risk.
He says market timing works, but the strategy he vaguely hints at requires faster reaction times than are likely to be achieved by the kind of investor this book seems aimed at.
His use of fractals doesn’t have any apparent value.
Mandelbrot is primarily a mathematician with limited interest in understanding how markets work. One clear example is his mention of a time when Magellan “was still a small fund, too small for any detractors to argue that its size alone gave it a competitive edge”. Any informed person should know that’s completely backward – larger funds have a clear disadvantage because they are limited to trading the most liquid investments.
Another example of a careless mistake is when he claims the evidence suggests basketball players have hot streaks, seemingly unaware that Tversky and others have largely debunked that idea.

Wall Street vs Intrade

Posted by Peter on September 29, 2008
Posted in: Idea Futures, Investing.

The stock market reacted to today’s defeat of the bank bailout bill with an unusually big decline. Yet the news wasn’t much of a surprise to people watching Intrade, whose contract BAILOUT.APPROVE.SEP08 was trading around 20% all morning. Why did the stock market act as if it was a big surprise?
Did Intrade traders make a lucky guess not based on adequate evidence? Did they have evidence that the stock market ignored? Could the stock market have priced in an 80% chance of the bill being defeated (if so, that would seem to imply that passage would have caused the biggest one-day rise in history)? Could the stock market have been reacting to other news which just happened to coincide with the House vote? (It looks like the market had a short-lived jump coinciding with news that House leaders hoped to twist enough arms to reverse the vote, but I wasn’t able to watch the timing carefully because I was at the dentist).

It seems like one of these must be true, but each once seems improbable.

Arnold Kling, whose comments on the bailout have been better than most, was surprised that the bill failed.

I covered a few of my S&P 500 futures short positions at near the end of trading, but I’m still positioned quite cautiously (I made a small profit today).