Argentan half-marathon 2016 [1:23:28-23/397-V2 2/?-16⁰]

And yet another Argentan half-marathon! Which started this blog, so to speak, 8 years ago… Although I could not repeat my feat at the San Francisco half-marathon, as I had lost my high altitude benefits, I managed well enough, with a good overall time of 1:23:28 and a second place in the V2 category, once again. I gained more than one minute from last year time, despite a strong face wind and thanks to sticking to a small group of younger runners. This is one of my best times since the start of the blog in 2008, so I am clearly very happy with the result. And plan to celebrate tonight with a top Montpellier wine!

The Magicians [#2]

In a minor key coincidence with my book review last week, I spotted this advertising board on my métro platform this morning. Announcing the diffusion of the first season of The Magicians on the French SyFy [sic] channel. (Next to this board, a more relevant one from Droit au Logement.)

Pu Erh [普洱茶]

Two massive pancakes of Pu Erh (Pǔ’ěr) [fermented] tea my student Changye brought me back from Yunnan (made by the factory that revolutionised the making of Pu Erh) and that I am looking forward tasting!

Bye, Rosetta!

Le Monde puzzle [#967]

A Sudoku-like Le Monde mathematical puzzle for a come-back (now that it competes with The Riddler!):

Does there exist a 3×3 grid with different and positive integer entries such that the sum of rows, columns, and both diagonals is a prime number? If there exist such grids, find the grid with the minimal sum?

I first downloaded the R package primes. Then I checked if by any chance a small bound on the entries was sufficient:

cale<-function(seqe){ 
 ros=apply(seqe,1,sum)
 cole=apply(seqe,2,sum)
 dyag=sum(diag(seqe))
 dayg=sum(diag(seqe[3:1,1:3]))
 return(min(is_prime(c(ros,cole,dyag,dayg)))>0)}

Running the blind experiment

for (t in 1:1e6){
  n=sample(9:1e2,1)
  if (cale(matrix(sample(n,9),3))) print(n)}

I got 10 as the minimal value of n. Trying with n=9 did not give any positive case. Running another blind experiment checking for the minimal sum led to the result

> A
 [,1] [,2] [,3]
[1,] 8 3 6
[2,] 1 5 7
[3,] 2 11 4

with sum 47.

advanced computational methods for complex models in Biology [talk]

Here are the slides of the presentation I gave at the EPSRC Advanced Computational methods for complex models in Biology at University College London, last week. Introducing random forests as proper summaries for both model choice and parameter estimation (with considerable overlap with earlier slides, obviously!). The other talks of that highly interesting day on computational Biology were mostly about ancestral graphs, using Wright-Fisher diffusions for coalescents, plus a comparison of expectation-propagation and ABC on a genealogy model by Mark Beaumont and the decision theoretic approach to HMM order estimation by Chris Holmes. In addition, it gave me the opportunity to come back to the Department of Statistics at UCL more than twenty years after my previous visit, at a time when my friend Costas Goutis was still there. And to realise it had moved from its historical premises years ago. (I wonder what happened to the two staircases built to reduce frictions between Fisher and Pearson if I remember correctly…)

trick or treat?!

Two weeks ago, we went to a local restaurant, connected to my running grounds, for dinner. While the setting in a 16th building that was part of the original Sceaux castle was quite nice, the fare was mediocre and the bill more suited for a one star Michelin than dishes I could have cooked myself. The height (or rather bottom) of the meal was a dish of sardines consisting in an half-open pilchard can… Just dumped on a plate with a slice of bread. It could have been a genius stroke from the chef had the sardines been cooked and presented in the can, alas it sounded more like the act of an evil genie! Or more plainly a swindle. As those tasty sardines came straight from the shop!