Thursday, April 27, 2006

A Hung Jury is Bad, But....

I was lecturing on Condorcet's "Jury Theorem."

It bears on many problems in political theory, but my point that day was that a group of schlubs (chance of being correct: 0.51) might be "smarter", if we require unanimity, than one well trained judge (chance of being correct: .95). The reason exploits statistical independence: the probabilities of 12 jurors all (independently) being wrong is very small. So a unanimous guilty verdict of people off the street is better than one smart judge. The chance of 12 .51 folks all, separately, being wrong is [(0.49)^12]=.0002. So, *if* the jury is unanimous in favor of one outcome, the chance that they are correct is .9998.

A student asked, "But what if the jury isn't unanimous?"

I said, "That may not be a bad thing; it means you aren't sure. And in our system, 'not sure' means NOT GUILTY."

A pause. Then is where I made my misstep. I wanted to compare juries with judges.

"If the jury is NOT uanimous, that's a hung jury. You know what to do with a hung jury. Either a misstrial, or just call it not guilty. BUT, what would you do with a hung judge?" I stopped, horrified; the students stared.

Then, a young woman at the back yelled: "Marry him!"

It took several minutes for order to be restored. And I still haven't quite recovered.

Men are Unnecessary III

The boys and I go out to our "man property." 35 acres of pine forest in Chatham County, south of Pittsboro.

We take provisions: many weapons, a wheelbarrow full of ammunition, 125 cc Suzuki dirt bike, bushels of Doritos, more sandwiches than anyone could ever want, umbrella, folding chairs....and we set up camp.

Then we work on the baseball field that we are building ("If you build it....nerds will come.") Field is shaping up well, will soon be ready for practice.

But the real reason is to do empirical experiments, and record the results. Our most recent experiment was to try to figure out how quickly you could take down a standing, but dead, 4 inch diameter pine tree with shotgun fire by firing at the base from ten yards. Two variables: steel shot/lead shot, and standard/magnum loads.

We kept good data, but the results were so predictable that it is only worth summarizing. No apparent difference in shot type, but magnum load reduces shots required between 30% and 50%. In terms of scale, the MOST it ever took was ten shots, and that was Monty Python ("I'm not dead yet!") tree that we shouldn't have included in the sample.

We also fired several boxes of 22 short shells. We just got a Ruger 10/22, and I have to say it is a whole of fun. We have two 30-round aftermarket banana clips, and the little Ruger is quite sturdy in terms of not jamming even if you fire as fast as you can pull the trigger. It took us a long time to get the scope sighted in, but with the scope set up correctly the gun is as accurate as you could possibly want.

I nailed a toilet seat to a 2x4 frame, over a shallow pit. These latrine facilities are not exactly appropriate for female use, not because they don't work (gravity is EVERYWHERE, I tell you!), but because the open air setting is not something most women would want to try out. For my own view, let me say there is something special about answering nature's call on a small hilltop, and being able to see at least 1/4 mile in all directions, as a gentle breeze blows through your private parts. You sit and think to yourself: MY land! This is MY land! And I am heavily armed! Or, I will be as soon as I get off this toilet seat.

Wednesday, April 26, 2006

Bad times

Sorry to be away so much. Very hard month.

But, on the plus side:

1. My good friend Stephen Wilkinson got tenure at Duke!

UPDATE: I misspelled Steven's name. My only excuse is that I was assuming he was using the old Brit trick of adding useless letters words, such as labour or colour. That way their books are longer with no additional effort. Anyway, sorry about that, Steffan!

2. My good friend Scott de Marchi got tenure at Duke!

3. Classes are over!

4. The Department finished its response to the external review report, and sent the response up to the Allen building.** This took days and days of "work," meaning the thing you do when you are too stupid to write anything useful or interesting. (UPDATE: Yes, I am talking about myself being too stupid to write anything useful or interesting. Being chair is like a lobotomy, except there is no scar and it pays better).

5. Neither of my sons play lacrosse.*

So, I'm feeling blessed.

(*UPDATE: earlier version said "plays." Sorry)

(**Quick: is refering to the university administration as "The Allen Building" an example of (choose all that apply)? :

a. Onomatepoeia
b. Synecdoche
c. Metonymy
d. Irony
e. Pomposity )

(UPDATE: actual pix of Wilkinson and de Marchi added after original post. Uncanny, right?)

Tuesday, April 11, 2006

Tax Wedgies

Interesting bit on taxes, via the FB.

Belgium, Germany and Hungary impose the highest taxes among OECD countries on the pay of a single person on average earnings, while Korea, Mexico and New Zealand take the least, according to the latest edition of the OECD’s annual publication Taxing Wages.

For a single-earner married couple with two children on average earnings, by contrast, Turkey, Sweden and Poland impose the biggest ‘tax wedge’, while Ireland, Iceland and the United States take the smallest slice in tax. Taxing Wages compares the shares of employee earnings taken by governments in OECD countries through taxation by calculating what it calls the ‘tax wedge’, the difference between labour costs to the employer and the net take-home pay of the employee, including any cash benefits from government welfare programmes.

In 2005, single individuals without children earning the average wage in services and manufacturing industries faced a tax wedge of 55.4% of the cost of their labour to their employers in Belgium, 51.8% in Germany and 50.5% in Hungary, compared with 17.3% in Korea, 18.2% in Mexico and 20.5% in New Zealand. The average for OECD countries was 37.3%. See Table 1.

For a one-earner married couple with two children on average earnings, the tax wedge ranged from 42.7% in Turkey, 42.4% in Sweden and 42.1% in Poland to 11.9% in the United States, 11% in Iceland and 8.1 % in Ireland. The average for OECD countries was 27.7%


Wednesday, April 05, 2006

Self Interest 1, Rawls 0

For the class today over at UNC, A. Rosenberg and I tried an exercise.

Not really a fair test of Rawls, but just thought we'd see.

We bought lottery tickets, enough for the whole class.

Before we handed them out, one per customer, we told the class they had to decide whether to (a) put all the class winnings into a pot, to be shared, or (b) each winner keeps his/her winnings. Alternative b won, about 2-1, in a class of 30.

Most people got nothing. Three people won a dollar. One young lady won $25. And got to keep it all.

So much for the Difference Principle....

Sunday, April 02, 2006

Parrish: The Thought

Carolyn Parrish watch.....

It has been more than a year now since I wrote about Carolyn Parrish

(excerpt: Carolyn Parrish: She stomped a George Bush doll, with boots (she had the boots, not the doll). On TV, on CBC-TV, in fact. Of course, the Missasauga (That's west of Toronto, just west of Etobicoke, actually) MP also critiqued the "coalition of idiots" Bush was leading in Iraq. Linda claimed that CP's real achievement was not getting ink for pounding Bush, but rather for finally getting Paul Martin (who kicked her out of caucus after much "Oh, my-ing") to make a decision on something. HE FIRED HER. I would say that this is a real achievement, but there is a deeper achievement to credit Ms. Parrish with. She hates Americans, but she sometimes talks to one, like Dorothy here. It seems clear that Carolyn Parrish is a loud-mouthed, impolite, unscrupulous self-promoting cretin. In other words, her real achievement is that SHE HAS BECOME an American, in spite of claiming to hate them.)

But...where is the old sea-hag now?

Well, she said this recently: "I think Canada's role in Afghanistan has morphed into something else now. It has morphed into an offensive role. I would prefer if we were involved in rebuilding and providing infrastructure."

Well, sure. Canada doesn't actually send much money to Afganistan. Or soldiers, for that matter. But wouldn't the world be a better place if people would just all get along? If Canadians in Afghanistan and Iraq would stop trying to defend themselves, and just go out and build some houses and roads....there's the ticket.

Streaming Video

When people say "streaming video", this is what they should mean. (If you have trouble with quicktime, there are other options here)

Note that the guys are actually trying. But the women, those few who would try it, are mostly just laughing at how ridiculous it must feel to be a guy, spraying things with Mr. Winkie.

Me? I want one of those target grids for the Mungo house, right away, connected to World of Warcraft. Can you imagine taking down infernals by remote streaming?

(Nod to Stefan. Only Germans can truly appreciate the absurd).

Saturday, April 01, 2006

Pre-publication bonus to M.E. readers

My newest essay on EconLib goes live soon.

But, it is up already, and you can check it out.


The economists I talked to weren't really surprised.

"People don't understand opportunity cost. For that matter, they don't understand lots of other apparently simple economics concepts. That's why we should study economics more."

I'm not sure this is right. It reminds me of Bill Niskanen's (1971) observation about Ludwig von Mises. Niskanen argued that many people, including von Mises, were too optimistic, resting their conclusions on "the hope, almost pathetic in retrospect, that a broader education in economics will reduce the popular support for large government and the consequent pervasive bureaucracy."


Why Men are not Really Necessary II continue the theme of "Are Men Necessary?" (my lovely wife, surrounded by huge hulking maleness, is not convinced), more evidence that the answer is....

Even if they are, WTF?

Here is how it went down: We (my sons and I; always their fault, not mine) were reading about the famous urban legend of the JATO rocket car, also famed Darwin Award retraction.

So...we got to thinking. We had some toy cars, and we had some rocket engines. And some of the toy cars and rocket engines were of the same RELATIVE scale as the JATO

Well, you can see for yourself: the engine is attached using a bunch of masking tape. The engine is an ESTES type B, pretty small (may be 3 Newton-seconds)

Now, there are two problems, as even a quick glance reveals. The car is large enough that there is angular force being generated around an axis that passes somewhere through the middle of the car. More simply, the engine is mounted (just as in the JATO story) in a way that might very well induce rotation as well as forward motion.

Second, the tape is a pretty half-assed attachment technique. At a minimum, we should have used duct tape, and covered the front so it couldn't scoot out from under the tape.

Well, the rotation test is the problem to be solved: would the car begin to fly, or would it spin? Spin....that's the answer. Movie evidence (a short .avi file)

A question: how big would the rocket engine have to be for its mass to dominate? It is not clear that JATO car would ever have gotten off the ground, instead of just being force nose first into a horrific forward roll on the highway.

Another test, soon: Much bigger car, D-type rocket engine (12-15 Newton-seconds). Stay tuned.

UPDATE, from NP, who being male is also unnecessary:

I have no idea if you guys watch Mythbusters or not but they did this myth in the first season. They got some pretty good data.

I will see if I can find a video but here are some links with more info on the full scale test.

Link 1

Link 2

Where Everything Isn't Meant to Be Okay

Drove back past Camp LeJeune today, in Jacksonville, NC.

Lots, and LOTS, of "we want our boy back" (mostly; sometimes girl) signs on the fence as you drive along NC-24 past the base.

That's why I don't get the "I support the Iraqi resistance" folks. I know a lot of people in the military, officers and enlisted both. My dad was a captain in the regular Army, WWII, southern France.

You want to say the war is a mistake, or that Bush is a bad President, go ahead.

And if you want to say the REAL victims here are the Iraqi civilians, you may be right.

But the hate directed toward the soldiers trying to do an impossible job, I just don't get. And there are lots of people who really do fancy that they think American soldiers should justly die for the mistakes of an American President.

I am not one of those people. And they also serve who stand and wait....