2124 search results for "twitter"

Really useful bits of code that are missing from R

January 10, 2011
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Really useful bits of code that are missing from R

There are some pieces of code that are so simple and obvious that they really ought to be included in base R somewhere. Geometric mean and standard deviation – a staple for anyone who deals with lognormally distributed data. geomean <- function(x, na.rm = FALSE, trim = 0, ...) { exp(mean(log(x, ...), na.rm = na.rm,

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Building a fact-based world view

January 7, 2011
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Building a fact-based world view

Gapminder is an independent foundation based in Stockholm, Sweden. Its mission is “to debunk devastating myths about the world by offering free access to a fact-based world view“. They provide free online tools, data (more than 400 datasets freely available!) and videos “to better understand the changing world“. The initial development of Gapminder was the

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Arrogance sampling

January 7, 2011
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Arrogance sampling

A new posting on arXiv by Benedict Escoto on a simulation method for approximating normalising constants (i.e. evidence) with an eye-catching name! Here is the abstract This paper describes a method for estimating the marginal likelihood or Bayes factors of Bayesian models using non-parametric importance sampling (“arrogance sampling”). This method can also be used to

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a survey on ABC

January 6, 2011
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a survey on ABC

With Jean-Michel Marin, Pierre Pudlo and Robin Ryder, we just completed a survey on the ABC methodology. It is now both arXived and submitted to Statistics and Computing. Rather interestingly, our first draft was written in Jean-Michel’s office in Montpelier by collating the ‘Og posts surveying new ABC papers! (Interestingly because this means that my

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web content anlayzer

January 6, 2011
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web content anlayzer

Just developed a small crawler to check my online content at binfalse.de in terms of W3C validity and the availability of external links. Here is the code and some statistics...

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Graph gallery in R

January 6, 2011
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Graph gallery in R

R is sometime criticized for producing graphs not as elaborated as Matlab ones, or other softwares’. Here is a link to a graph gallery by Romain François to “enhance your data visualization with R”. The corresponding R code is given. Might be useful for ENSAE students for ‘statap’ projects. Below are four examples. The maps

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Short review of the R book

January 5, 2011
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Short review of the R book

David Scott wrote a review of Introducing Monte Carlo Methods with R in the International Statistical Review that is rather negative, since the main bulk reads as follows: I found some aspects of the book very disappointing. The first chapter (“Basic R Programming”) has some unfortunate mistakes and some statements, which are contentious at least

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My first R package: zipcode

January 5, 2011
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My first R package: zipcode

My first package, zipcode, is now available on CRAN. It contains the CivicSpace database of 43,191 U.S. zip codes.

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Adap’skiii [day 2]

January 5, 2011
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Adap’skiii [day 2]

Another exciting day at Adap’skiii!!! Yves Atchadé presented a very recent work on the fundamental issue of estimating the asymptotic variance estimation for adaptive MCMC algorithms, with an intriguing experimental observation that a non-converging bandwidth with rate 1/n was providing better coverage than the converging rate. (I always found the issue of estimating the asymptotic

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Le Monde puzzle [52|solution]

January 1, 2011
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Le Monde puzzle [52|solution]

I have now received the first issue of Le Monde magazine, including the solution to puzzle #52 I solved just in time by simulated annealing! The trick is in using the following theorem: Iter(1,x,y) is divisible by 10x-1 if and only if y is divisible by 10x-1. Then the value to be found is divisible

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