October 21, 2014

1:10 PM | Questions and answers from Cal Poly
On a recent visit to California Polytechnic State University, I met a lot of great folks and was asked several good questions about teaching and learning. Here are some of my answers.
11:05 AM | Guest post: The dangers of evidence-based sentencing
This is a guest post by Luis Daniel, a research fellow at The GovLab at NYU where he works on issues dealing with tech and policy. He tweets @luisdaniel12. Crossposted at the GovLab. What is Evidence-based Sentencing? For several decades, parole and probation departments have been using research-backed assessments to determine the best supervision and treatment […]

October 20, 2014

10:14 PM | control functionals for Monte Carlo integration
This new arXival by Chris Oates, Mark Girolami, and Nicolas Chopin (warning: all colleagues & friends of mine!) is a variation on control variates, but with a surprising twist namely that the inclusion of a control variate functional may produce a sub-root-n (i.e., faster than √n) convergence rate in the resulting estimator. Surprising as I […]
8:51 PM | Fund Samuel Hansen’s kickstarter
Hopefully this isn’t too little, too late: you should fund Samuel Hansen’s kickstarted Relatively Prime: Series 2, an excellent series of long-form “stories from the mathematical domain”. Samuel is the creative force behind such excellent science podcasts as Combinations and Permutations, Strongly Connected Components, Science Sparring Society, and (with Peter Rowlett) Math/Maths, and he did […]
6:20 PM | Domaine Ollier Taillefer [Faugères]
Filed under: Travel, Wines Tagged: carignan, Faugères, grenache, Languedoc, mourvèdre, red wine, Syrah
3:00 PM | Margins of error on Atlanta-area traffic signs
Every work day, in the evening on the way home, I pass a sign on Georgia 400 a few miles north of I-285. On a good day it will read something like: “I-285: 4-6 MIN / I-85: 11-13 MIN” and on a bad day it’ll read something like “I-285: 10-12 MIN / I-85: 32-34 MIN” […]
2:12 PM | Three ways to present a probability forecast, and I only like one of them
To the nearest 10%: To the nearest 1%: To the nearest 0.1%: I think the National Weather Service knows what they’re doing on this one. The post Three ways to present a probability forecast, and I only like one of them appeared first on Statistical Modeling, Causal Inference, and Social Science.
1:00 PM | On deck this week
Mon: Three ways to present a probability forecast, and I only like one of them Tues: Try a spaghetti plot Wed: I ain’t got no watch and you keep asking me what time it is Thurs: Some questions from our Ph.D. statistics qualifying exam Fri: Solution to the helicopter design problem Sat: Solution to the […] The post On deck this week appeared first on Statistical Modeling, Causal Inference, and Social Science.
12:14 PM | Paradosso cosmico
The Time Machine at the End of the World, di Les Edwardsvia ahiddenworld.tumblr.comCome tutti i generi, anche la fantascienza in ultima analisi è interessata a parlare dell'essere umano. In particolare, come ricorda Isaac Asimov, parla dell'essere umano contemporaneo, nascondendo il messaggio dietro una rappresentazione meravigliosa, dietro un sense of wonder dovuto a progressi scientifici inimmaginabili.I due progressi scientifici che muovono la maggior parte della fantascienza (non […]

Gödel K. (1949). An Example of a New Type of Cosmological Solutions of Einstein's Field Equations of Gravitation, Reviews of Modern Physics, 21 (3) 447-450. DOI:

Silk J. (1970). The Instability of a Rotating Universe, Monthly Notices of the Royal Astronomical Society, 147 (1) 13-19. DOI:

Deutsch D. (1991). Quantum mechanics near closed timelike lines, Physical Review D, 44 (10) 3197-3217. DOI:

Deutsch, D. & Lockwood, M. (1994). The Quantum Physics of Time Travel, Scientific American, 270 (3) 68-74. DOI: 10.1038/scientificamerican0394-68

Buser M., Kajari E. & Schleich W.P. (2013). Visualization of the Gödel universe, New Journal of Physics, 15 (1) 013063. DOI:

Sorli A., Fiscaletti D. & Gregl T. (2013). New insights into Gödel's universe without time, Physics Essays, 26 (1) 113-115. DOI:

Ringbauer M., Broome M.A., Myers C.R., White A.G. & Ralph T.C. (2014). Experimental simulation of closed timelike curves, Nature Communications, 5 DOI:

11:03 AM | Big Data’s Disparate Impact
Take a look at this paper by Solon Barocas and Andrew D. Selbst entitled Big Data’s Disparate Impact. It deals with the question of whether current anti-discrimination law is equipped to handle the kind of unintentional discrimination and digital redlining we see emerging in some “big data” models (and that we suspect are hidden in a bunch more). […]
3:45 AM | Personification and pseudoscience
If you study the philosophy of science — and sometimes even if you just study science — then at some point you might get the urge to figure out what you mean when you say ‘science’. Can you distinguish the scientific from the non-scientific or the pseudoscientific? If you can then how? Does science have […]

October 19, 2014

10:14 PM | Shravan Vasishth at Bayes in Paris this week
Taking advantage of his visit to Paris this month, Shravan Vasishth, from University of Postdam, Germany, will give a talk at 10.30am, next Friday, October 24, at ENSAE on: Using Bayesian Linear Mixed Models in Psycholinguistics: Some open issues With the arrival of the probabilistic programming language Stan (and JAGS), it has become relatively easy […]
7:31 PM | Alan Guth, eternal inflation and the multiverse about #AlanGuth #multiverse #CosmicInflation #icep2014 At the beggining of October, Alan Guth was at the workshop Fine-Tuning, Anthropics and the String Landscape at Madrid, and he concluded his talk with the following slide: The complete talk, without question time, follows:He presented the same talk also at ICEP 2014:
6:36 PM | LOG#157. Superstatistics (II).
Following the previous article, now I will discuss some interesting points in the paper: Generalized information entropies depending only on the probability distribution, by O.Obregón and A.Gil-Villegas. You can find the paper here The Boltzmann factor for a generalized … Continue reading → Tags:  effective entropy, equipartition principle, equipartition theorem, F-distribution function, fractal, gamma distribution function, […]
6:36 PM | LOG#156. Superstatistics (I).
This post is the first of three dedicated to some of my followers. Those readers from Mexico (a nice country, despite the issues and particularities it has, as the one I live in…), ;). Why? Well, …Firstly, they have proved … Continue reading → Tags:  Beck, Bekenstein-Hawking formula, Boltzmann, Boltzmann factor, classical statistical mechanics, Cohen, complex systems, corrections to newton gravity, entropic gravity, Entropy, equipartition principle, […]
6:01 PM | Maples
5:56 PM | Pippo e l'arte moderna
da Topolino e il ladro di quadri, dall'edizione uscita per il Tascabilone #8
3:24 PM | Links for October 19
John Cook spoke at KeenCon on Bayesian statistics as a way to integrate intuition and data. A fantasy sports wizard’s winning formula, from Brad Reagan at the Wall Street Journal. Via Hacker News. From Dan Egan of Betterment, It’s About Time in the Market, Not Market Timing, an analysis of the distribution of returns based […]
1:54 PM | “Your Paper Makes SSRN Top Ten List”
I received the following email from the Social Science Research Network, which is a (legitimate) preprint server for research papers: Dear Andrew Gelman: Your paper, “WHY HIGH-ORDER POLYNOMIALS SHOULD NOT BE USED IN REGRESSION DISCONTINUITY DESIGNS”, was recently listed on SSRN’s Top Ten download list for: PSN: Econometrics, Polimetrics, & Statistics (Topic) and Political Methods: […] The post “Your Paper Makes SSRN Top Ten List” appeared first on […]
12:31 PM | Aunt Pythia’s advice
Quick, get on the bus! Hurry! Aunt Pythia is gonna be super fast this morning because she’s got crepes to make and apples to pick. Are you ready? Belts buckled? OK great, let’s do this. And afterwards: please think of something to ask Aunt Pythia at the bottom of the page! By the way, if […]
12:18 PM | more geese…
Filed under: pictures, Running Tagged: geese, Parc de Sceaux
12:37 AM | Hiatus
Hiatus Hi everyone. You probably haven’t heard from me in a while. This is because I have been completely overwhelmed by class work this semester, which has prevented me from doing the things I want to do, like blogging and doing … Continue reading → The post Hiatus appeared first on The Physics Mill.

October 18, 2014

10:14 PM | a week in Warwick
This past week in Warwick has been quite enjoyable and profitable, from staying once again in a math house, to taking advantage of the new bike, to having several long discussions on several prospective and exciting projects, to meeting with some of the new postdocs and visitors, to attending Tony O’Hagan’s talk on “wrong models”. […]
9:32 PM | Hideout
Ad attirarmi sono stati innanzitutto i disegni: precisi e dettagliati, giocano moltissimo con i bianchi e i neri. Sono infatti opportunamente luminosi nelle scene cittadine, le più tranquille, e sono pesantemente bui nelle scene ambientate nel bosco o nella prigione sotterranea dove si trovano i protagonisti della vicenda, una coppia di giovani in crisi coniugale alla ricerca, apparentemente, di una soluzione ai loro problemi.In un fumetto dell'orrore, ad ogni modo, la parte grafica ha […]
6:54 PM | FINAL CFP and *EXTENDED DEADLINE*: SoTFoM II 'Competing Foundations?', 12-13 January 2015, London.
The focus of this conference is on different approaches to the foundations of mathematics. The interaction between set-theoretic and category-theoretic foundations has had significant philosophical impact, and represents a shift in attitudes towards the philosophy of mathematics. This conference will bring together leading scholars in these areas to showcase contemporary philosophical research on different approaches to the foundations of mathematics. To accomplish this, the conference has […]
1:43 PM | Hoe noem je?
Haynes Goddard writes: Reviewing my notes and books on categorical data analysis, the term “nominal” is widely employed to refer to variables without any natural ordering. I was a language major in UG school and knew that the etymology of nominal is the Latin word nomen (from the Online Etymological Dictionary: early 15c., “pertaining to […] The post Hoe noem je? appeared first on Statistical Modeling, Causal Inference, and Social Science.
12:11 PM | Experts vs Professionals
Working with professionals can be a joy. Not only can they solve your problem, they may help you see what problem you should solve. I’ve had several instances lately when I hired a pro to do something I’d attempted myself. In each case I was very pleased and wondered why I hadn’t done this sooner. […]

October 17, 2014

10:14 PM | art brut
Filed under: Kids, pictures, Travel Tagged: Barbamama, Barbapapa, bicycle, mountain bike, Paris
9:09 PM | I macachi del giappone
Vi parlerò di due isole, Kojima, la più grande, e Torishima, per metà nascosta dietro l'altra. Entrambe ospitano branchi di macachi selvatici. Ci fu un tempo in cui l'intera isola di Kyushu pullulava di queste scimmie, tuttavia in seguito all'invasione dell'uomo ne sono rimasti solo pochi gruppi sporadici, perlopiù su isolette remote come queste. Le scimmie locali sono le meno influenzate dall'uomo e, in quanto tali, oggetto di studi approfonditi da parte dei […]
7:37 PM | Flutter: Butterfly Sanctuary
I know that most of this month, so far, was more about the Mathematicians’ Event and I believe sometimes it is to much, even if I love this event a lot. So I decided to do something completely new today: … Continue reading →
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