Eric Rasmusen's Weblog

Ecclesiology Questions

admin — Tue, 22 Jul 2008 03:08:09 +0000

My cumulative ecclesiology page, a list of questions and, at some point, discussion and answers in the style of Aquinas’s Summa, is here. I will add the post below to it.

Should books be sold in a church?

Should there be commercial advertising in a church bulletin?

Should money be collected in an offering during worship?

Should worship be beautiful?

Should children have rattles and drums to use during hymnsinging in worship?

Should a church have songs to which the congregation does not sing along?

Should there be clapping after someone has sung or played during worship?

Should children run the service sometimes?

Should there be patronage in choosing a minister?

Should the KJV Bible be used?

Should a person bring his own bible to church?

Should a church have pew bibles?

Is it wrong if members of the congregation do not dress formally, e.g. in jacket and tie?

Is it wrong if members of the congregation dress sloppily, e.g. in shorts and t-shirts?

Should women wear hats in church?

Trying out Google’s Blogger

admin — Sat, 29 Sep 2007 21:20:37 +0000

I am unhappy with Wordpress for various reasons, so I’m trying out Google’s Blogger. For a while I will be posting at http://www.rasmusen.org/t instead.

Weighted Least Squares and Why More Data is Better

erasmuse — Fri, 28 Sep 2007 10:21:01 +0000

In doing statistics, when should we weight different observations differently?

Suppose I have 10 independent observations of $x$ and I want to estimate the population mean, $\mu$. Why should I use the unweighted sample mean rather than weighting the first observation .91 and each of the rest by .01?

Either way, I get an unbiased estimate, but the unweighted mean gives me lower variance of the estimator. If I use just observation 1 (a weight of 100% on it) then my estimator has the variance of the disturbance. If I use two observations, then a big positive disturbance on observation 1 might be cancelled out by a big negative on observation 2. Indeed, the worst case is that observation 2 also has a big positive disturbance, in which case I am no worse off by having it. I do not want to overweight any one observation, because I want mistakes to cancel out as evenly as possible.

All this is completely free of the distribution of the disturbance term. It doesn’t rely on the Central Limit Theorem, which says that as $n$ increases then the distribution of the estimator approaches the normal distribution (if I don’t use too much weighting, at least!).

If I knew that observation 1 had a smaller disturbance on average, then I *would* want to weight it more heavily. That’s heteroskedasticity.

Lizzy’s Plus Table

erasmuse — Thu, 27 Sep 2007 18:48:01 +0000

Who Most Wants To Be Elected Policeman?

erasmuse — Wed, 26 Sep 2007 19:00:02 +0000

Jerusalem Post via National Review

Two weeks after Israel’s alleged bombing raid in Syria, which some
foreign reports said targeted North Korean nuclear material, the UN’s
nuclear watchdog elected Syria as deputy chairman of its General
Conference on Monday.
(more…)

Bayesian vs. Frequentist Statistical Theory

erasmuse — Tue, 25 Sep 2007 19:00:02 +0000

The Frequentist view of probability is that a coin with a 50% probability of heads will turn up heads 50% of the time.

(more…)

Asymptotics

erasmuse — Mon, 24 Sep 2007 09:29:02 +0000

Page 96 of David Cox’s 2006 Principles of Statistical
Inference has a very nice one-sentence summary of asymptotic theory:

[A]pproximations are derived on the basis that the amount of
information is large, errors of estimation are small, nonlinear
relations are locally linear and a central limit effect operates to
induce approximate normality of log likelihood derivatives.

An Online Quiz

erasmuse — Sun, 23 Sep 2007 04:08:01 +0000

You scored as Evangelical Presbyterian, You’re an Evangelical Presbyterian, probably a member of a PCA church. Sound theology and reverent worship are important to you, but so are outreach and ministry to the community. You are likely to be from the deep South, and perhaps at one time you were Southern Baptist.

Evangelical Presbyterian

80%

Moderate Evangelical

55%

Fightin’ Fundy

55%

Reformed Baptist

50%

Baptist

50%

High Church Nomad

30%

Presby - Old School

30%

Conservative Evangelical

20%

What Kind of Evangelical Are You
created with QuizFarm.com

A Rejection Letter

erasmuse — Sat, 22 Sep 2007 00:00:02 +0000

I received a rejection letter recently that puzzles me. My co- authors and I don’t really see how the criticisms below apply to our paper, apart from the single spacing and not citing any articles from that journal. We would welcome any comments. Don’t worry about being overly frank. We are especially interested in whether Empirical Finance has some customary style we are not following. Here is the paper’s abstract:

(more…)

Greenspan Criticizes Bush for Money, but not for Duty

admin — Fri, 21 Sep 2007 09:38:36 +0000

Peggy Noonan’s “Now He Tells Us: If only they’d listened to Greenspan! And they might have, if only he’d spoken clearly” is good on how the former Fed chairman has saved his criticism of pork barrel spending for his book rather than making it when it might have actually stopped the spending:

(more…)

Throwing Away Plastic Bottles as a Solution to Global Warming

admin — Thu, 20 Sep 2007 10:59:22 +0000

Has anyone pointed out that large landfills full of plastic bottles and disposable diapers are a solution to global warming?

(more…)

The Northern Rock Bank Run

admin — Wed, 19 Sep 2007 10:53:13 +0000

The Northern Rock bank run is interesting (background below from a newspape account). I’ll make three points: 1. Stupidly low deposit insurance limits caused a rational run, 2. The government should have made Northern Rock pay for the free full deposit guarantee it just got, and 3. It’s time to get out of savings accounts and bank stock shares if you’re British..

(more…)

Exclusive Dealing and Foreclosure

admin — Tue, 18 Sep 2007 22:40:56 +0000

Someone asked me about the past few years’ papers on exclusive dealing, so I did some thinking. I’ll lay it out in my own way.

Suppose we have 100 buyers, each with 1% of the market, one upstream incumbent seller who charges the monopoly price. Everybody knows that in a year a potential entrant seller will arise, and that he will need 15% of the market to achieve the necessary scale economies.

(more…)

Every Child Reaching His Potential— A Realistic, but Limited, Goal

admin — Mon, 17 Sep 2007 09:16:41 +0000

“Intelligence in the Classroom: Half of all children are below average, and teachers can do only so much for them” by Charles Murray in the WSJ, is a good article. The subtitle says it all. In designing a school system, we need to think about children’s potential, not just what we’d like for them to be able to learn. Wherever we set a threshold, some children aren’t going to be able to make it. (more…)

Spontaneouse Generation and Evolution

admin — Sun, 16 Sep 2007 21:17:06 +0000

p>Three Hierarchies makes the nice point that if you look closely, the Bible does not say that God directly created animals and plants, just that He created the earth, and that spontaneous generation– as opposed to God having created all living things directly— was long accepted by Christians and everyone else. It was only in the 1800’s that scientists showed that life comes from life, so that the origins of life became a puzzle: (more…)

A Good Cartoon

admin — Sat, 15 Sep 2007 22:01:04 +0000

The Robert Marks Academic Freedom Case at Baylor

admin — Fri, 14 Sep 2007 08:56:13 +0000

Baylor University is clearly infringing on academic freedom when it tries to shut down Professor Robert Marks’s pro-intelligent-design website, located here with the disclaimers the professor put on in response to Baylor’s complaints that people might think Baylor officially approved of his research. I wish there were more publicity about this kind of thing. Even if a professor believes in astrology, if that’s his research, he should be allowed to pursue it, if not necessarily give pay raises as a result. Of course, a professor’s astrology page would *not* be shut down– it is precisely the plausbility of intelligent design that infuriates its opponents. They take its threat seriously. For an article in WORLD, see here.

The Odds Ratio in Biased-Sample Case-Control Studies

admin — Thu, 13 Sep 2007 14:40:31 +0000

I learned something this morning. When you’re trying to estimate the impact of a two-valued X on some two-valued Y with Y=1 being a rare event, you can get an unbiased estimate of the relative risk, Pr(Y=1|X=1)/Pr(Y=1|X=0), even if your sample is biased because you oversampled mainly Y=1 observations. This is not just restricted to logit estimation either. I learned this reading The analysis of case-control studies by NE Breslow and NE Day, but I have a writeup at http://www.rasmusen.org/x/2007/oddsratio.pdf that is much clearer.

A Cartoon

admin — Tue, 11 Sep 2007 16:00:13 +0000

width= "240" >

LSE’s Computerized Seminar Sign-Up List

admin — Mon, 10 Sep 2007 10:08:39 +0000

The London School of Economics has a great idea: a computerized seminar sign-up list. You choose the seminars that interest you, and get email notifications.