# Posts

### June 27, 2014

+

5:02 AM | Dobby is a free elf

It must be graduation-and-moving-out time again. Seen this morning, in the parking lot of a UCI apartment complex for postdocs and visiting researchers:

### June 26, 2014

+

10:14 PM | thermodynamic Monte Carlo

Michael Betancourt, my colleague from Warwick, arXived a month ago a paper about a differential geometry approach to relaxation. (In the Monte Carlo rather than the siesta sense of the term relaxation!) He is considering the best way to link a simple base measure ϖ to a measure of interest π by the sequence where […]

+

4:53 PM | (Py, R, Cmd) Stan 2.3 Released

We’re happy to announce RStan, PyStan and CmdStan 2.3. Instructions on how to install at: http://mc-stan.org/ As always, let us know if you’re having problems or have comments or suggestions. We’re hoping to roll out the next release a bit quicker this time, because we have lots of good new features that are almost ready […]
The post (Py, R, Cmd) Stan 2.3 Released appeared first on Statistical Modeling, Causal Inference, and Social Science.

+

4:51 PM | No Averages

Here is an old Olympiad problem:
Prove that you can choose 2k numbers from the set {1, 2, 3, …, 3k−1} in such a way that the chosen set contains no averages of any two of its elements.
a2a_linkname="No Averages";
a2a_linkurl="http://blog.tanyakhovanova.com/?p=504";
[...]

+

1:07 PM | Estimating a customer satisfaction regression, asking only a subset of predictors for each person

Aurangzeb Agha writes in with an interesting question: I’d like to speak with you briefly to get your thoughts on the imputation of missing data in a new online web-survey technique I’m developing. Our survey uses Split Questionnaire Design. The total number of surveys will vary in length with different customers, but will generally be […]
The post Estimating a customer satisfaction regression, asking only a subset of predictors for each person appeared first on Statistical
[…]

+

12:56 PM | On British Values and British Nature

‘Pride’ has always struck me a peculiar and entirely inappropriate way to express your feelings about your homeland. After all, the accident of having been born somewhere is hardly something over which you had either any choice or any control. But for all that, I’m certainly happy enough to call Britain ‘home’; and despite having had the good fortune to visit some wonderful parts of the world, and to work with people from many different countries, I have never […]

+

11:36 AM | Unsolicited advice about having kids

You know how it’s better to have a discussion with someone when you’re calm and they haven’t just done something that drives you absolutely nuts? Well I’m going to generalize to the parenting advice realm: best time to give parenting advice is not when you’ve just seen a kid get poorly parented or a parent […]

### June 25, 2014

+

10:14 PM | did I mean endemic? [pardon my French!]

Deborah Mayo wrote a Saturday night special column on our Big Bayes stories issue in Statistical Science. She (predictably?) focussed on the critical discussions, esp. David Hand’s most forceful arguments where he essentially considers that, due to our (special issue editors’) selection of successful stories, we biased the debate by providing a “one-sided” story. And […]

+

8:39 PM | Elliott Bay and TGK

One final note about the book tour — Elliot Bay Book Company, who handled sales at my talk in Seattle, won a special place in my heart forever, because not only did they have lots of copies of How Not To Be Wrong, they also brought along a small stack of The Grasshopper King! And they even […]

+

6:35 PM | Events

Finally is full holiday for me, exams are finished and results are up. So refreshing and I am happy that all my hard works was worth it (so far). For this summer I have some events I would like to … Continue reading →

+

There are a number of ways to construct the real numbers , for instance as the metric completion of (thus, is defined as the set of Cauchy sequences of rationals, modulo Cauchy equivalence); as the space of Dedekind cuts on the rationals ; as the space of quasimorphisms on the integers, quotiented by bounded functions. […]

+

3:50 PM | On tweetcasting

After a travel- and conference-induced silence over the past months, we're back from the ECMTB in Gothenburg with some fresh thoughts for new posts. To start, Alex Fletcher, Linus Schumacher and Jacob Scott discuss a newly fashionable conference activity: tweetcasting.An increasing number of academics are using twitter professionally. One popular usage is tweetcasting presentations at conferences. This can range from advertising your own or your peer's research to live commenting - essentially
[…]

+

1:58 PM | More on those randomistas

Following up on our recent post, I clicked on some of Ziliak’s links and found lots of good stuff, especially the post by Berk Ozler. I have no knowledge of his work but I like his writing; see here, for example. Ziliak replied: Ozler’s post is very good indeed, and well written. Ozler’s suggestion for […]
The post More on those randomistas appeared first on Statistical Modeling, Causal Inference, and Social Science.

+

12:57 PM | Lazy Jokes

* * *
—Describe yourself in three words.
—Lazy.
* * *
Internet forum:
—Tell me about yourself.
—I am lazy and I like to eat.
—Tell me some more.
—I am tired of typing. I’ll go grab a snack.
* * *
—Why do you want to divorce your wife?
—She nags too much. For the last half six month, she’s been bugging me [...]

+

12:56 PM | A Logic Quiz

This is a variation on an old quiz. Can you answer the last question?
—An airplane carries 500 bricks. One of the bricks falls out. How many bricks are left in the airplane?
—This is easy: 499!
—Correct. Next question. How do you put a giraffe into a refrigerator?
—Open the refrigerator, put in the giraffe, and close [...]

+

12:30 PM | Iterative linear solvers as metaphor

Gaussian elimination is systematic way to solve systems of linear equations in a finite number of steps. Iterative methods for solving linear systems require an infinite number of steps in theory, but may find solutions faster in practice. Gaussian elimination tells you nothing about the final solution until it’s almost done. The first phase, factorization, […]

+

11:39 AM | The dark matter of big data

A tiny article in The Cap Times was recently published (hat tip Jordan Ellenberg) which describes the existence of a big data model which claims to help filter and rank school teachers based on their ability to raise student test scores. I guess it’s a kind of pre-VAM filtering system, and if it was hard […]

+

2:53 AM | Food I ate

Of course the really important thing about traveling isn’t seeing old friends or selling books, it’s eating things you can’t eat at home. So here’s my list of some notable things I ate. The Koji Uehara burger at Mr. Bartley’s. A new one, very good. With onion rings, of course. Peking ravs at the Hong […]

### June 24, 2014

+

11:26 PM | The Cubic Ball of the 2014 FIFA World Cup

I know this sounds crazy. Even stupid. But Adidas did design a cubic ball, called brazuca, for the 2014 World Cup. And, yet, this cubic ball is rounder than any previous ball in football History. How is it possible? This article explains it.

+

10:14 PM | ABC model choice by random forests

After more than a year of collaboration, meetings, simulations, delays, switches, visits, more delays, more simulations, discussions, and a final marathon wrapping day last Friday, Jean-Michel Marin, Pierre Pudlo, and I at last completed our latest collaboration on ABC, with the central arguments that (a) using random forests is a good tool for choosing the […]

+

Readers probably saw this already, but I mention it anyhow. Physicist Sean Carroll has a 23 June 2014 post, "Physicists should stop saying silly things about philosophy", on his blog gently criticizing some recent anti-philosophy remarks by some well-known physicists, and trying to emphasize some of the ways physicists and philosophers of physics might interact constructively on foundational/conceptual issues. Interesting comments underneath too.

+

Yup, another social psychology researcher from northwestern Europe who got results that people just don’t believe. I’m a fan of Retraction Watch but not a regular reader so I actually heard about this one indirectly, via this email from Baruch Eitam which contained the above link and the following note: Of the latest troubles in […]
The post Too Linear To Be True: The curious case of Jens Forster appeared first on Statistical Modeling, Causal Inference, and Social Science.

+

12:18 PM | editor’s nightmare

Filed under: Books, Kids, pictures, University life Tagged: Fermat, Fermat's theorem, fonts, NIPS, proceedings, xkcd

+

12:00 PM | Multiple zeta

The Riemann zeta function, introduced by Leonard Euler, is defined by where the sum is over all positive integers n. Euler also introduced a multivariate generalization of the zeta function where the sum is over all decreasing k-tuples of positive integers. This generalized zeta function satisfies the following beautiful identity: The multivariate zeta function and […]

+

11:56 AM | You are not Google’s customer

I’m going to write one of those posts where many of you will already understand my point. In fact it might be old hat for a majority of my readers, yet it’s still important enough for me to mention just in case there are a few people out there who don’t know how the modern […]

+

2:58 AM | HNTBW Publicity Roundup 4

Newspaper reviews are starting to come in. Manil Suri at the Washington Post: Ellenberg’s talent for finding real-life situations that enshrine mathematical principles would be the envy of any math teacher. He presents these in fluid succession, like courses in a fine restaurant, taking care to make each insight shine through, unencumbered by jargon or […]

### June 23, 2014

+

10:14 PM | revenge of the pigeons

While I had not had kamikaze pigeons hitting my windows for quite a while…, it may be that one of them decided to move to biological warfare: when I came back from Edinburgh, my office at the University was in a terrible state as a bird had entered through a tiny window opening and wrecked […]

+

7:46 PM | Alice in gabbia

A maggio sono andata con mio fratello al salone del libro di Torino e tra i tanti acquisti comprai questo libro. Fu amore a prima vista, anzi a prima lettura... di quarta di copertina! Appena lessi, appunto, la quarta di copertina, pensai "Deve essere mio!"La frase che mi colpì fu questa:Sono quasi tre anni adesso che lavoro e che ho perso ogni facoltà di vivere il mondo. Se splende il sole, piove o nevica la mia vita procede indifferente: 8 ore davanti al pc. E se ci pensate
[…]

+

3:45 PM | Sympathy for Scott Walker

The Milwaukee Journal-Sentinel suggests that the slow pace of job creation in Wisconsin, not recall campaign shenanigans, may be Scott Walker’s real enemy in his upcoming re-election campaign: In each of Walker’s first three years, Wisconsin has added private-sector jobs more slowly than the nation as whole, and the gap is sizable. Wisconsin has averaged […]

+

3:30 PM | Smullyan and the Randomistas

Steve Ziliak wrote in: I thought you might be interested in the following exchanges on randomized trials: Here are a few exchanges on the economics and ethics of randomized controlled trials, reacting to my [Zilliak's] study with Edward R. Teather-Posadas, “The Unprincipled Randomization Principle in Economics and Medicine”. Our study is forthcoming in the Oxford […]
The post Smullyan and the Randomistas appeared first on Statistical Modeling, Causal Inference, and Social
[…]