# Monthly Archives: April 2011

April 14, 2011
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For my second lecture today, I need to plot a likelihood surface for a basic two-component mixture with only the means unknown: here is the R code to speed up things llsurf=function(trumyn=2.,wayt=.3,var2=1.,ssiz=500){ # draws the log-likelihood surface and a random sample sd2=sqrt(var2) parti=(runif(ssiz)>wayt) sampl=(1-parti)*rnorm(ssiz)+parti*(trumyn+sd2*rnorm(ssiz)) mu2=mu1=seq(min(sampl),max(sampl),.1) mo1=mu1%*%t(rep(1,length(mu2))) mo2=(rep(1,length(mu2)))%*%t(mu2) ca1=-0.5*mo1*mo1 ca2=-0.5*mo2*mo2 like=.1*(ca1+ca2) # log prior N(0,10) for

## R 2.13.0 released

April 13, 2011
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The R Core Group has released the latest update to open-source R, R 2.13.0 is now available. You can download the new source distribution from the R Project website, and I see from the Download R tool at inside-R.org that binaries for Windows and Mac are already available at my local CRAN mirror (and, shortly, yours too). The (long)...

## Le Monde puzzle #13

April 13, 2011
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This week, Le Monde offers not one but three related puzzles: Is it possible to label the twelve edges of a cube by consecutive numbers such that the sum of the edge numbers at any of the eight nodes is constant? Is it possible to label the eight nodes of a cube by consecutive numbers

## compiler and runiregGibbs (bayesm)

April 13, 2011
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So everyone's excited about the new R 2.13 release because of the compiler package.Apparently it is easy to get a 3x speed increase by simply compiling a function.Doing a lot of the MCMC stuff, I am particularly excited about speed in R. I just compile...

## compiler and runiregGibbs (bayesm)

April 13, 2011
By

So everyone's excited about the new R 2.13 release because of the compiler package.Apparently it is easy to get a 3x speed increase by simply compiling a function.Doing a lot of the MCMC stuff, I am particularly excited about speed in R. I just compile...

## Rcpp 0.9.4, and a paper in the Journal of Statistical Software

April 13, 2011
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A brand new 0.9.4 release of Rcpp is now on CRAN and Debian. This version contains an improvement to loading and initialization of Rcpp modules, a bug fix for vectors of factors, another build issue fix as well as (per common practice with JSS) ...

## Block diagonal matrices in R

April 13, 2011
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As far as I can tell, R doesn’t have a function for building block diagonal matrices so as I needed one, I’ve coded it myself. It might save someone some time. Example: Let m1 and m2 two square matrices. Selec … Continue reading →

## Some comments peer-review and a year of blogging

April 13, 2011
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It's been a year since I began keeping a web log. This post presents some thoughts related to the experience. Blogging is Sharing Ideas Blogging is online self-publishing. There is no faster way to share your ideas so broadly. Last year at the useR! conference (in Gaithersburg, MD, just a few months after I started

## RProtoBuf 0.2.3

April 13, 2011
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A maintenance release 0.2.3 of RProtoBuf is now on CRAN. RProtoBuf provides GNU R bindings for the Google Protobuf data encoding library used and released by Google. The NEWS file entry follows below: 0.2.3 2011-04-12 o Protect UINT64...

## Using R and clinical heuristics to explore the Heritage Health Prize: what do we gain?

April 13, 2011
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The recent opening of the Heritage Health Prize both represents a milestone and raises a cautionary flag. On the one hand, crowdsourced analytics prizes have never tackled anything so noble (not to discount predicting movie ratings), but on the other … Continue reading →