Blog Archives

Jonathan Rougier – Nomograms for visualising relationships between three variables (useR! 2011)

August 16, 2011
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Jonathan Rougier – Nomograms for visualising relationships between three variables (useR! 2011)

Background: Donkeys in Kenya. Tricky to find the weight of a donkey in the “field” – no pun intended! So using a few measurements,  estimate the weight. Other covariates include age. Standard practice is to fit: for adult donkeys, and other slightly different models for young/old and ill donkeys. What can a statistician add: Add

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Ulrike Gromping – Design of Experiments in R

August 16, 2011
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Ulrike Gromping – Design of Experiments in R

Example: Car seat occupation: Algorithm must decide whether airbag opens: Must open for adult but not for small child or if the seat if empty a few others I missed. Key questions are: What type of design: 32 run regular fractional factorial Response measurement – depends on dummy position, so repeat for 3 different dummy

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High Performance Computing

August 16, 2011
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High Performance Computing

Wilem Ligtenberg – GPU computing and R Why GPU computing – theoretical GFLOPs for a GPU is three times greater than a CPU. Use GPUs for same instruction multiple data problems (SIMD). Initially GPUs were developed for texture problems. For example, a wall smashed into lots of pieces. Each core handled a single piece. CUDA

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Kaleidoscope Ic (useR! 2011)

August 16, 2011
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Kaleidoscope Ic (useR! 2011)

These are my rough notes on the Kaleidoscope Ic session. David Smith – The R Ecosystem (useR! 2011) David Smith works for Revolution Analytics. Quick overview of the R project – useR, r-journal, and r-forge. Social media starting to play a part in R – Google+, twitter, stackoverflow, and the traditional R mailing list. The

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Brian Ripley – The R Development Process (useR! 2011)

August 16, 2011
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Brian Ripley – The R Development Process (useR! 2011)

There are my notes on the User2011 invited talk. Brian Ripley has been a member of R core since 1998 The R Development Process – A insideR’s view R Timeline: JCGS paper submitted in 1995. 1997: CRAN(Mar), Core team(Aug), CVS (Sept) R 1.0.0 Feb 2000 – 2.8MB. Many people don’t take 0.X.X seriously R 2.0.0 Oct

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Paul Murrell – Introduction to Grid graphics (useR! 2011)

August 15, 2011
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Paul Murrell – Introduction to Grid graphics (useR! 2011)

Typically, I’m very bad at taking notes in conference. This time around, I intend to make notes for each some of the talks I attend at this year’s useR! 2011 conference. Below are my notes that I made during this afternoon’s tutorial. Note: these are just notes I made and aren’t meant to be a

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Character occurrence in passwords

June 16, 2011
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Character occurrence in passwords

As everyone knows, it seems that Sony is taking a bit of a battering from hackers.  Thanks to Sony, numerous account and password details are now circulating on the internet. Recently, Troy Hunt carried out a brief analysis of the password structure. Here is a summary of his post: There were around 40,000 passwords, of which

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Makefiles and Sweave

May 12, 2011
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Makefiles and Sweave

A Makefile is a simple text file that controls compilation of a target file. The key benefit of using Makefile is that it uses file time stamps to determine if a particular action is needed. In this post we discuss how to use a simple Makefile that compiles a tex file that contains a number

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“An R package” or “A R package”

March 26, 2011
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“An R package” or “A R package”

I’m currently writing some lecture notes on R and I used the phrase “a R package” without thinking. Since the word following the article “a” was a consonant, I automatically went for “a” instead of “an”. The problem is that “R” sounds likes a vowel, so “a R package” grates on the listener. The correct

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Graphical Display of R Package Dependencies

March 23, 2011
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Graphical Display of R Package Dependencies

In some work that I am currently involved in, we have to decide which GUI engine we should use. As an obvious starter, we decided to have a look at what other people are using in their packages. While cran helpfully displays all the R packages that are available, it doesn’t (I don’t think), give

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