November 28, 2014

11:29 PM | 254A, Supplement 1: A little bit of algebraic number theory (optional)
Analytic number theory is only one of many different approaches to number theory. Another important branch of the subject is algebraic number theory, which studies algebraic structures (e.g. groups, rings, and fields) of number-theoretic interest. With this perspective, the classical field of rationals , and the classical ring of integers , are placed inside the […]
11:14 PM | Moon over Soho [book review]
A book from the pile I brought back from Gainesville. And the first I read, mostly during the trip back to Paris. Both because I was eager to see the sequel to Rivers of London and because it was short and easy to carry in a pocket. “From the figures I have, I believe that two to […]
8:07 PM | Mathematics in ‘Spiral: The Bonds of Reasoning’
This couple of weeks I have been reading a lot of manga. I have liked some anime for a long time, but never had the courage to read manga. But for some reason I have downloaded an app on my … Continue reading →
6:42 PM | Mega inanity
Since the lead up to the Turing centennial in 2012 celebrating the birth of one of the great meta-mathematicians of the twentieth century, Alan Mathison Turing, I have observed with increasing horror the escalating hagiographic accounts of Turing’s undoubted historical … Continue reading →
2:39 PM | Arizona plagiarism update
More details on the Matthew Whitaker case from Brian Gratton and from Rick Shenkman. Shenkman even goes to the trouble of interviewing some of the people involved. It’s not pretty. One of the people involved in this sad, sad story, is Michael Crow, formerly at Columbia and currently president of the University of Arizona, about […] The post Arizona plagiarism update appeared first on Statistical Modeling, Causal Inference, and Social Science.
2:33 PM | Bell’s Theorem Way
A street in Belfast is to be named after the late John Stewart Bell, a quantum physicist whose work has had a huge impact on modern physics and quantum information theory. Bell passed away in 1990, before he could be awarded a Nobel prize for his work, and Belfast Council have agreed to name a... Read more »
12:06 PM | LaTeX Something Something Darkside
[This is week 3 of the challenge. Ok, I’m stretching “every week” a bit here. I blame somebody’s first cold or alternatively Turkeys. Also, I cheated; this took longer than 30mins.] Darth Vader/Stewie: Oh, come on, Luke, come join the …

November 27, 2014

11:14 PM | Le Monde puzzle [#887quater]
And yet another resolution of this combinatorics Le Monde mathematical puzzle: that puzzle puzzled many more people than usual! This solution is by Marco F, using a travelling salesman representation and existing TSP software. N is a golden number if the sequence {1,2,…,N} can be reordered so that the sum of any consecutive pair is a […]
6:14 PM | Thanksgiving power law
In honor of Thanksgiving: take a look at Niall MacKay’s paper Of bombs and boats and mice and men: a random tour through some scaling laws. I mention this because one of the scaling laws there is the time it … Continue reading →
2:51 PM | Quantitative literacy is tough! Or, I had no idea that, in 1958, 96% of Americans disapproved of interracial marriage!
Mark Palko linked to this data-rich cartoon by Randall Munroe: And I was stunned, first by the data on interracial marriage and then, retrospectively, by my earlier ignorance of these data. Was approval of interracial marriage only 4% in 1958? I had no idea. I looked it up at the Gallup site and it seems […] The post Quantitative literacy is tough! Or, I had no idea that, in 1958, 96% of Americans disapproved of interracial marriage! appeared first on Statistical Modeling, Causal […]
12:34 PM | How to ignore your family on Thanksgiving
There has been lots of advice lately on how to have a civil conversation at Thanksgiving – NPR ran a piece yesterday on “topics both Democrats and Republicans enjoy”, for example, which made me slightly annoyed and amused – perhaps because I am neither – and inspired this somewhat alternative list of ways to enjoy […]
7:25 AM | Trees that represent bandwidth
In my algorithms class today, I covered minimum spanning trees, one property of which is that they (or rather maximum spanning trees) can be used to find the bottleneck in communications bandwidth between any two vertices in a network. Suppose the network edges are labeled by bandwidth, and we compute the maximum spanning tree using these labels. Then between any two vertices the path in this tree has the maximum bandwidth possible, among all paths in the network that connect the same two […]

November 26, 2014

11:14 PM | Le Monde puzzle [#887ter]
Here is a graph solution to the recent combinatorics Le Monde mathematical puzzle, proposed by John Shonder: N is a golden number if the sequence {1,2,…,N} can be reordered so that the sum of any consecutive pair is a perfect square. What are the golden numbers between 1 and 25? Consider an undirected graph GN […]
3:13 PM | Combing Food and Formulas
A long time ago, I had this idea in mind: if I could be a better cooker I could make people around me understand more about geometry (2D, 3D shapes or higher dimensions). I believe that food has a way … Continue reading →
3:13 PM | L'Europa da ragione ai precari
Periodo instabile, questo. Quel che riesco a scrivere è tutto frutto di motivazioni così forti che, in un periodo più tranquillo avrebbero fruttato post a raffica. E' anche per questo (e non solo per non tenere fermo il blog troppo a lungo, come ultimamente) che pubblico questa news dall'Europa, giratami grazie a una mailing list di precari: La Corte di Giustizia Europea sbarra la strada al lavoro precario. Docenti e Ata della scuola con più di 36 mesi di servizio […]
2:30 PM | Leif and Uri need to hang out with a better class of statisticians
Noted psychology researchers and methods skeptics Leif Nelson and Uri Simonsohn write: A recent Psych Science (.pdf) paper found that sports teams can perform worse when they have too much talent. For example, in Study 3 they found that NBA teams with a higher percentage of talented players win more games, but that teams with […] The post Leif and Uri need to hang out with a better class of statisticians appeared first on Statistical Modeling, Causal Inference, and Social Science.
1:18 PM | Methodological developments in evolutionary genomic [3 years postdoc in Montpellier]
[Here is a call for a post-doctoral position in Montpellier, South of France, not Montpelier, Vermont!, in a population genetics group with whom I am working. Highly recommended if you are currently looking for a postdoc!] Three-year post-doctoral position at the Institute of Computational Biology (IBC), Montpellier (France) : Methodological developments in evolutionary genomics. One young […]
12:16 PM | Emacs resources
This is the second in my series of posts pointing out resources on my site. This week’s topic is Emacs. Emacs kill (cut) commands Emacs point (cursor) movement Getting started with Emacs on Windows Notes on Unicode in Emacs See also the Twitter account UnixToolTip and blog posts tagged Emacs. Last week: Miscellaneous math notes […]
1:49 AM | Grothendieck's Activism And What It Says About The World
Ivar Ekeland's reflections on the activist phase of Grothendieck's life.

November 25, 2014

11:14 PM | reflections on the probability space induced by moment conditions with implications for Bayesian Inference [refleXions]
“The main finding is that if the moment functions have one of the properties of a pivotal, then the assertion of a distribution on moment functions coupled with a proper prior does permit Bayesian inference. Without the semi-pivotal condition, the assertion of a distribution for moment functions either partially or completely specifies the prior.” (p.1) […]
6:14 PM | Lecture videos from Trends in Logic XIV
Lecture videos from TiL XIV are now available here.
2:38 PM | I (almost and inadvertently) followed Dan Kahan’s principles in my class today, and that was a good thing (would’ve even been more of a good thing had I realized what I was doing and done it better, but I think I will do better in the future, which has already happened by the time you read this; remember, the blog is on a nearly 2-month lag)
As you might recall, the Elizabeth K. Dollard Professor says that to explain a concept to an unbeliever, explain it conditionally. For example, if you want to talk evolution with a religious fundamentalist, don’t try to convince him or her that evolution is true; instead preface each explanation with, “According to the theory of evolution […] The post I (almost and inadvertently) followed Dan Kahan’s principles in my class today, and that was a good thing […]
2:25 PM | In breve: la cascata dei barioni
In maniera semplice si può parlare di meccanica quantistica nel momento in cui si descrivono le proprietà delle particelle utilizzando i numeri interi. Fatti quei primi passi all'inizio del XX secolo, come fisici abbiamo descritto le particelle utilizzando i così detti numeri quantici in grande abbondanza: la loro scoperta era sempre legata alla scoperta di nuovi decadimenti che non potevano essere altrimenti spiegati senza violare la conservazione di un qualche numero […]

Gell-Mann, M. (1964). A schematic model of baryons and mesons, Physics Letters, 8 (3) 214-215. DOI: 10.1016/S0031-9163(64)92001-3

Alvarez L., Eberhard P., Good M., Graziano W., Ticho H. & Wojcicki S. (1959). Neutral Cascade Hyperon Event, Physical Review Letters, 2 (5) 215-219. DOI:

Chatrchyan, S. et al (CMS Collaboration) (2012). Observation of a New $\Xi_b$ baryon, Physical Review Letters, 108 (25) DOI: 10.1103/PhysRevLett.108.252002

Barnes V., Connolly P., Crennell D., W. Delaney, W. Fowler, P. Hagerty, E. Hart, N. Horwitz, P. Hough & J. Jensen & (1964). Observation of a Hyperon with Strangeness Minus Three, Physical Review Letters, 12 (8) 204-206. DOI:

2:10 PM | 4+1 Interview: Linda Nilson
What is "specifications grading", and could it precipitate a revolutionary change in how faculty assess student work in higher education? In this 4+1 interview, we chat with Linda Nilson, director of the Office of Teaching Effectiveness and Innovation at Clemson University, about her latest book _Specifications Grading: Restoring Rigor, Motivating Students, and Saving Faculty Time_ and the idea of specs grading.
Editor's Pick
1:44 PM | Is tourism in Haiti inherently exploitative?
I recently returned from Haiti, where I was a tourist traveling around the country for 6 days with my friends Jamie and Becky. As I spent time there, I felt increasingly aware of the difficult if not miserable spot that the country as a whole finds itself in, even though there are of course wonderful […]
1:00 PM | First two impressions of statistics
When I was a postoc I asked a statistician a few questions and he gave me an overview of his subject. (My area was PDEs; I knew nothing about statistics.) I remember two things that he said. A big part of being a statistician is knowing what to do when your assumptions aren’t met, because […]
8:12 AM | LIPIcs formatting tricks
If, like me, you're working on a SoCG submission, and this is the first time you've tried using the LIPIcs format that SoCG is now using, you may run into some minor formatting issues (no worse than the issues with the LNCS or ACM formats, but new and different). Here are the ones I've encountered, with workarounds where I have them:The LIPIcs format automatically includes several standard LaTeX packages including babel, amsmath, amsthm, amssymb, and hyperref. So there's no point in including […]
6:00 AM | Thin folding
I have another new preprint on arXiv this evening: Folding a Paper Strip to Minimize Thickness, arXiv:1411.6371, with six other authors (Demaine, Hesterberg, Ito, Lubiw, Uehara, and Uno); it's been accepted at WALCOM.The basic goal of this is to try to understand how to measure the thickness of a piece of paper that has been folded into a shape that lies flat in the plane. For instance, in designing origami pieces, it's undesirable to have too much thickness, both because it wastes paper […]

November 24, 2014

11:14 PM | prayers and chi-square
One study I spotted in Richard Dawkins’ The God delusion this summer by the lake is a study of the (im)possible impact of prayer over patient’s recovery. As a coincidence, my daughter got this problem in her statistics class of last week (my translation): 1802 patients in 6 US hospitals have been divided into three […]
3:36 PM | The hype cycle starts again
Completely uncritical press coverage of a speculative analysis. But, hey, it was published in the prestigious Proceedings of the National Academy of Sciences (PPNAS)! What could possibly go wrong? Here’s what Erik Larsen writes: In a paper published in the Proceedings of the National Academy of Sciences, People search for meaning when they approach a […] The post The hype cycle starts again appeared first on Statistical Modeling, Causal Inference, and Social Science.
237 Results