Thursday, November 29, 2012

Not Random Links.

  1. A very interesting read: "Broaden Your Horizons by Randomizing Your Reading Material" (h/t Ali). Since reading "The Diceman" by George Cockcroft (on the right below "BOOKS THAT MADE AN IMPACT ON ME") I have a random number generator on my phone that is normally used to select what to eat from a menu. And, now I'm here in the Netherlands, whether I should go to University by bike or foot (the latter is more healthy, but takes 15 minutes longer).
  2. Pics from the WGAPE meeting last May at UC Berkeley.
  3. The movie "Stealing Africa" on Dutch TV: info here. Why Zambia doesn't profit from higher prices of copper. Answer: the big foreign companies earn the money and avoid paying tax in Zambia. (h/t Maarten)
  4. This is brilliant. A randomly generated math paper was accepted to the "Advances in Pure Mathematics". Read also the reviews by the referees: a.o. "We can’t catch the main thought from this abstract." Duh!
  5. Interesting read about the administor-faculty ratio at universities. Mmm. Maybe I should become an administrator. They also seem to earn more. (h/t Jenn)
  6. Interesting post on iRevolution on the use of email data to estimate international migration rates. See also this for very interesting work done by Blumenstock in Rwanda by making use of cellphones.  

Monday, November 26, 2012

BBC's "Masters of Money": Keynes, Hayek, Marx.

Presented by Stephanie Flanders (BBC's economics editor), "Masters of Money" is a 2012 three-episode BBC documentary about Keynes, Hayek, and Marx (each their own episode). It's quite good (h/t Carlos):

The first episode about John Maynard Keynes:

Saturday, November 24, 2012

As events are unfolding in and around Goma.

A blog about the Congo, and mainly about my experiences in Eastern Congo, and I still haven't written about the current events taking place in and around Goma. Well, there are people reporting about this in a much more informed and better way than I could ever do. Please follow among others @texasinafrica; @jasonkstearns; @kvlassen; and @schlindweinsim on Twitter about how events are unfolding.

Today yet another expat friend safely arrived in Bujumbura. I'm happy about that. Unfortunately, my Congolese enumerators, many of them I now consider friends, are still in the area. Yesterday one of them uploaded the picture and text below on Facebook:

"Merci de prier pour la fin de la guerre en Rd Congo. Pensez à tous ces enfants abandonnées, sans parents ... Clique J'aime et écris ta prière en faveur de ce pays au coeur de l'Afrique. Que Dieu vienne en aide mon pays la RD Congo !!!"

With some of them (both Goma and Bukavu) I'm in almost daily contact and they're doing ok. I don't belief much in praying as the quote wants us to do, but I do hope that: 1) President Kagama has told and keeps on telling the M23 to "behave", and that 2) the FARDC and others do not go on pillage (and worse) sprees.

Thursday, November 8, 2012

And how long is your… survey?

When waiting for my plane at JFK last Monday, I was asked to fill out a survey. The US Department of Transport (DOT) wanted to know about the behavior of travelers in order to improve JFK airport. Good initiative, but how useful is a survey like this? It's not random at all! Most people said 'no' when the surveyor asked people to fill out the questionnaire. I said 'yes', but only because I'm doing survey work myself and felt for the surveyor. Let's say that the population consists out of 1% friendly people, and that only friendly people (and the rare confused grad-student) say 'yes' to a survey. Let's say that in this world only friendly people like candy-machines, and that that is what they suggest in the survey as an improvement to the airport. The DOT will thus conclude that "100% of people surveyed want candy-machines" and will spend a lot of money to build candy-machines at JFK. But they’ll build 90% too many of them! It’s a bit stupid example, but you see the point. One needs a proper random sample, and just asking people on the fly is really not doing that.
But there is another problem. When I was about 2 minutes into the survey I was no longer interested and, to be very honest, didn't really read more than half of the question before answering. My answers were probably off several times. Now I'm probably particularly quick to lose interest in things, but what does this say about the quality of answers to, for example, lengthy surveys we conduct in Africa for research?

It's our enumerator sitting comfy in that chair. :)

The DOT survey (at least that’s what was written on the front page) takes around 15 minutes. The survey we conducted in the Congo between 2010-2011 with around 10,000 households, took on average two hours! The design can be found here. Now, of course, I'm a particularly impatient person (much more than any African villager I have met). Moreover, our enumerators sit down with the respondents and ask the questions to them instead of the respondent filling out the survey alone. But still, two hours on average per survey cannot do the quality of replies much good.

Of course this was not the first time we thought about this. Two years ago, when creating the design documents, we were very well aware of this potential problem. As a result, we implemented the survey with two variations to learn about this:
  1. Random ordering of questions: The first variation was the random ordering of a set of questions. That is, half of the surveys (randomly selected) had sections ordered as X Y Z, and another half of the surveys had the order: X Z Y. 
  2. Mandatory break: Second, in half of the surveys (randomly selected) we instituted a mandatory break. We were able to do this because we did not make use of hardcopy surveys, but PDAs. We had programmed the PDA in such a way that at a certain point it would say “Now take a 30 minutes break”, and the PDA would be blocked for 30 minutes. The idea here is that after taking a break the person being interviewed (and the surveyor) would start fresh again improving the quality of the responses. 
Needless to say we added several trick questions to the surveys in order to measure whether people answered carefully. By doing so we can now learn whether the length of the survey is important.

Wednesday, November 7, 2012

Wageningen University: Here I come.

After a cancelled flight last week due to Hurricane Sandy, I'm currently at Heathrow waiting for my flight to Amsterdam. Destination: the Development Economics Group (DEG) at Wageningen University and Research, where I will be a pre-doctoral researcher during November and December.

I look much forward for two reasons. First, I'll by away from all the districtations in New York. While I have several papers up and running, the most important one (the jobmarket paper) still has to be written. I have many ideas but have not yet had the time to sit down and write it. Second, I expect the DEG a really good place to be. There are a set of researchers doing very interesting work on the political economy of development (impact evaluations, lab-in-the-field-experiments), and I look forward working together. As a start: I'm presenting tomorrow at their seminar.