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NullVoid » 2010 » August NullVoid » 2010 » August

Archive for August, 2010


Friday, August 27th, 2010 -- By ET

I came across a senior professor in Statistics in the hall way. He noticed that I moved my office.

I told him that the new office has a window, and my research productivity increased by 5 times.

He then said:”Wonderful, they should have installed 2 windows for you.”


German Publicity

Thursday, August 26th, 2010 -- By ET

This blog recently saw a big surge in the number of visitors from Germany. With a little tracing, I found the following website: http://www.handelsblatt.com/politik/wissenswert/studie-wie-wikipedia-markttheorien-widerlegt;2640653;0

The website is called “Handelsblatt Economy Newsletter” that reports “New trends in economics and business administration”.

It’s purely in German and the article specifically talks about the forthcoming AER paper Feng and I wrote about Wikipedia.

I used Google to translate the article, and it looks quite nice to me.

========Translated Article Below=========

LONDON. What a mistake. In the summer of 2002 reported the “Berliner Zeitung” as one of the first German media over the Internet Wikipedia – fascinated, but also skeptical: “But like the reservoir of knowledge also have large audiences and continually grow: In the near future it will not succeed, well, works of reference such as the Brockhaus outdo. “No six years later, told the Brockhaus publishing the end for the printed dictionary with – and Wikipedia now one of the most frequently visited Internet sites worldwide. Tens of thousands are working for free, voluntarily and without any fee.

A success story that brings economists provide explanations. Their traditional theories suggest that it would not even have the rise of the Internet lexicon may be. Why should rational individuals make the effort to write encyclopedia articles free of charge for an anonymous audience? Any Internet user can use the Online Encyclopedia, without himself contributes articles.

Thus, Wikipedia is what economists call a “public good” – an offer that will benefit all the people and by the use of which no one can be excluded. Classic examples of this are dikes and street lights. For public goods, so budding economists learn in basic, there is a big dilemma: There are strong incentives to freeloaders – to seize the offer without providing anything in return. The traditional economics postulates: the greater the number of potential beneficiaries, the more problems arise with free riders.

At least with Wikipedia is exactly the opposite is the case, shows a new study that appears in the upcoming “American Economic Review: The greater the number of potential readers, the more people are willing to devote their working hours for the online encyclopedia – probably because they draw mental satisfaction from the fact that their text be read by many others.

The scientists Xiaoquan Zhang (Hong Kong University of Science and Technology) and Feng Zhu (University of Southern California) have this effect after the example of the Chinese Wikipedia page. They use the fact that the government in Beijing has repeatedly censored the site due to politically unwelcome information. From October 2005, for example, were Internet users in China, the Wikipedia page does not call for nearly a year. By blocking the target audience of Wikipedia has reduced drastically over night. Million Internet users were suddenly excluded. For Chinese people in Taiwan, Hong Kong and the rest of the world, the page remained available, however.

What impact that had on the activities on the website? The researchers focused on the behavior of users outside the People’s Republic of China – people who, despite barring further access to the site and could change them. Zhang and Zhu use the fact that all changes are recorded in detail in texts on the Wikipedia page, and conceivably relate to the country in which the authors live. They compared the activities in Wikipedia immediately before and after the lock. They noted: With the start of the blockade itself have Chinese-language Internet users outside the People’s Republic of considerably less interest in Wikipedia – suddenly they wrote fewer new contributions and extended existing texts much rarer.

“The participation of authors is not blocked by the blockade decreased on average by 42.8 percent,” the economists note. The reason: The level of cooperation in Wikipedia procure satisfaction of the individual authors – researchers are referring to “social benefit”. “The shrinking group size reduces this benefit,” they write.

One indication of this is precisely the authors, where the social aspect of Wikipedia was very important and intensively romped in the discussion boards of the lexicon, wrote at the beginning of the barrier significantly less. “Our study provides empirical evidence that social effects may be stronger than the tendency to freeloaders,” the bottom line.

The study shows once again: economists make a mistake when they explain to the people to pure egoists – they can not explain many phenomena of real life properly.

Fixing CrossOver in Snow Leopard 10.6

Wednesday, August 18th, 2010 -- By ET

An update of the system broke my almost-perfect installation of Bakoma Tex in Mac OS X 10.6 through Crossover.

It took me a few months to suffer from this tragedy. Each time when I need to work with LaTeX, I need to load my Windows 7 from bootcamp. I tried to reset the Java Virtual Machine and so on, but it could not fix the problem.

Then today I thought about the error message it gave when I tried to open CrossOver. It says “can’t load ‘/system/library/perl/extras/5.10.0…”, so it strikes me that maybe it is Perl that needs fixing.

I went to /usr/bin to list perl versions:
/usr/bin$ ls -l perl*
lrwxr-xr-x 1 root wheel 9 Aug 18 10:50 perl -> perl5.10.0
-rwxr-xr-x 1 root wheel 86000 Jun 24 2009 perl.old
-rwxr-xr-x 1 root wheel 51200 Jun 24 2009 perl5.10.0
-rwxr-xr-x 1 root wheel 34816 Jun 24 2009 perl5.8.9
-rw-rw-rw- 34 root wheel 807 Jun 24 2009 perlbug
-rwxr-xr-x 1 root wheel 38307 Jun 24 2009 perlbug5.10.0
-rwxr-xr-x 1 root wheel 45068 Jun 24 2009 perlbug5.8.9
-rw-rw-rw- 34 root wheel 807 Jun 24 2009 perlcc
-rwxr-xr-x 1 root wheel 17983 Jun 24 2009 perlcc5.8.9
-rw-rw-rw- 34 root wheel 807 Jun 24 2009 perldoc
-rwxr-xr-x 1 root wheel 255 Jun 24 2009 perldoc5.10.0
-rwxr-xr-x 1 root wheel 254 Jun 24 2009 perldoc5.8.9
-rw-rw-rw- 34 root wheel 807 Jun 24 2009 perlivp
-rwxr-xr-x 1 root wheel 12309 Jun 24 2009 perlivp5.10.0
-rwxr-xr-x 1 root wheel 12304 Jun 24 2009 perlivp5.8.9
-rw-rw-rw- 34 root wheel 807 Jun 24 2009 perlthanks
-rwxr-xr-x 1 root wheel 45068 Jun 24 2009 perlthanks5.8.9

Perl 5.10.0 is a 64 bit version. So I downgraded the perl to perl 5.8.9 by the following commands:

sudo rm perl
sudo ln -s perl5.8.9 perl

Then it worked like a charm.

Traits of Successful Business Executives

Friday, August 13th, 2010 -- By ET

I’m doing some literature review for a paper of mine. I came across the following paper:

The Business Executive: The Psychodynamics of a Social Role

By: William E. Henry

The American Journal of Sociology, Vol. 54, No. 4, Industrial Sociology (Jan., 1949), pp. 286-291.


It was written in 1949, and talks about the common characteristics of successful business executives. Typically I do not find these descriptive papers useful, but it is interesting to see how people in 1949 perceive what executives should do to be successful.

The paper listed the following personality patterns that are common for success:

    Achievement Desires
    Mobility Drive
    Idea of Authority
    Ability to Organize Unstructured Situations
    Strong Self-Structure
    Apprehension and the Fear of Failure
    Activity and Aggression
    Strong Reality Orientation
    Different Interpersonal Relations with respect to Superiors and Subordinates
    Broken Tie with his own Parents
    Dependency Feelings and Concentration Upon Self

That was a long list, if you check these on people we know, say Steven Jobs, you would probably be amazed how accurate these items can “predict” his success. I’m constantly suspicious of this type of work because they obviously miss the sample of failed cases. It could be the case that people who share these traits fail more, but due to the sample selection problem, we cannot observe them. What if some other factors are driving the success of these people, and they just learned to behave in this way (i.e., behaving in this way does not produce success.)?

This brings back to the argument of my paper: when people assume social roles, they behave according to the perceived traits of these roles. In many situations, the list of characteristics is a result of being successful, not a source of it.

Run Robust Regression in R

Sunday, August 8th, 2010 -- By ET

Here is how:

model1 < - lm(dev ~ ind1 + ind2) sandwich(model1) vcovHC(model1, type = "HC")

Manual for Bureaucracy

Saturday, August 7th, 2010 -- By ET

Found the following amusing piece from http://rasmusen.dreamhosters.com/b/2010/06/oss-on-bureaucracy-and-sabotage/

“Simple Sabotage Field Manual”

(1) Insist on doing everything through “channels.” Never permit short-cuts to be taken in order to expedite decisions.

* * *

(3) When possible, refer all matters to committees, for “further study and consideration.” Attempt to make the committees as large as possible–never less than five.

(4) Bring up irrelevant issues as frequently as possible.

(5) Haggle over precise wordings of communications, minutes, resolutions.

(6) Refer back to matters decided upon at the last meeting and attempt to re-open the question of the advisability of that decision.

(7) Advocate “caution.” Be “reasonable” and urge your fellow-conferees to be “reasonable” and avoid haste which might result in embarrassments or difficulties later on.

(8) Be worried about the propriety of any decision–raise the question of whether such action as is contemplated lies within the jurisdiction of the group or whether it might conflict with the policy of some higher echelon.


Friday, August 6th, 2010 -- By ET

大陆是什么都不能做,包括法律允许 的。

Marshmallow Experiment – A Video.

Thursday, August 5th, 2010 -- By ET

I wrote about Marshmallow experiment a while ago.

Now here is a video:

I wonder how this test can pass the human-subject approval. For sure, these kids (except the little girl who ate it immediately) will be harmed and haunted for the life…

Unlocked iPhone 4 is Cheapest in HK

Tuesday, August 3rd, 2010 -- By ET

I guess there is no point of not buying it now.

This, however, is related to another psychological bias: people compare options in terms of gains/losses with respect to a reference point, not with respect to wealth. I’m happy to buy the iphone because I learned it is a good bargain in HK, not because I believed it delivers that much utility to me (although probably it will).

I think this figure should be on every HK iphone seller’s ad, I bet the effectiveness would give the highest ROI.

Market Efficiency Test

Monday, August 2nd, 2010 -- By ET

I’m here in Singapore for a 2-week summer institute of behavioral economics/finance. Vince Crawford, Matthew Rabin, Ted O’Donoghue and Terry Odean are the speakers.

Some keywords that surface frequently in the discussions are “bounded rationality”, “market efficiency”, “human bias”, “anomalies” etc.

This reminds me of a joke:
An economics professor and a student were strolling through the campus.
“Look,” the student cried, “there’s a $100 bill on the ground!”
“No, you are mistaken,” the professor replied. “That cannot be. If there were actually a $100 bill, someone would have picked it up.”

That is probably the most famous joke about economists. The professor is certainly a believer of Market Efficiency.

Next watch the video:


What makes all passers-by to ignore the wallet? Are lay-people suddenly believers of market efficiency?

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