Causal inferences — what Big Data cannot give us .[embedded content] The central problem with the present ‘Machine Learning’ and ‘Big Data’ hype is that so many — falsely — think that they can get away with analyzing real-world phenomena without any (commitment to) theory. But — data never speaks for itself. Data by themselves are useless. Without a prior statistical set-up, there actually are no data at all to process. Clever data-mining tricks are not...
Read More »The 25 Best Econometrics Blogs
The 25 Best Econometrics Blogs Yours truly, of course, feels truly honored to find himself on the list of the world’s 25 best econometrics blogs. 1. Bruno Rodrigues 7. Eran Raviv Blog Statistics and Econometrics 9. How the (Econometric) Sausage is Made 14. Lars P Syll Pålsson Syll received a Ph.D. in economic history in 1991 and a Ph.D. in economics in 1997, both at Lund University. He became an associate professor in economic history in 1995 and has since...
Read More »Econometric testing
Debating econometrics and its shortcomings yours truly often gets the response from econometricians that “ok, maybe econometrics isn’t perfect, but you have to admit that it is a great technique for empirical testing of economic hypotheses.” But is econometrics — really — such a great testing instrument? Econometrics is supposed to be able to test economic theories. But to serve as a testing device you have to make many assumptions, many of which themselves cannot be tested or...
Read More »The econometric illusion
What has always bothered me about the “experimentalist” school is the false sense of certainty it conveys. The basic idea is that if we have a “really good instrument” we can come up with “convincing” estimates of “causal effects” that are not “too sensitive to assumptions.” Elsewhere I have written an extensive critique of this experimentalist perspective, arguing it presents a false panacea, andthat allstatistical inference relies on some untestable assumptions … Consider...
Read More »Combinatorics (VI)
In my library, there are n philosophy books and six economics books. If yours truly can choose two books of each type in 150 ways, how many philosophy books are there in my library?
Read More »Do complex numbers exist? (wonkish)
Do complex numbers exist? (wonkish) .[embedded content]
Read More »Christmas combinatorics
Yours truly has invited five of his colleagues to share a Christmas lunch with him around the circular dinner table in his kitchen. Unfortunately, two of the colleagues are not on speaking terms with each other, so they cannot be seated together. In how many ways can we be seated around the table?
Read More »Weekend combinatorics (V)
An easy one this week: Yours truly wants to distribute 30 one-dollar coins among his kids Linnea, David, and Tora. In how many ways can this be done if he wants all of them to get at least one coin?
Read More »Monte Carlo simulations — no substitute for thinking
Monte Carlo simulations — no substitute for thinking In some fields—physics, geophysics, climate science, sensitivity analysis, and uncertainty quantification in particular—there is a popular impression that probabilities can be estimated in a ‘neutral’ or ‘automatic’ way by doing Monte Carlo simulations: just let the computer reveal the distribution … Setting aside other issues in numerical modeling, Monte Carlo simulation is a way to substitute...
Read More »Freedman’s Rabbit Theorem
In econometrics one often gets the feeling that many of its practitioners think of it as a kind of automatic inferential machine: input data and out comes causal knowledge. This is like pulling a rabbit from a hat. Great, but as renowned statistician David Freedman had it, first you must put the rabbit in the hat. And this is where assumptions come into the picture. The assumption of imaginary ‘superpopulations’ is one of the many dubious assumptions used in modern...
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