Publications by Markus Gesmann
Hodgkin-Huxley model in R
One of the great research papers of the 20th century celebrates its 60th anniversary in a few weeks time: A quantitative description of membrane current and its application to conduction and excitation in nerve by Alan Hodgkin and Andrew Huxley. Only a few weeks after Andrew Huxley died, 30th May 2012, aged 94.In 1952 Hodgkin and Huxley published...
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Reminder: Next Kölner R User Meeting 6 July 2012
This post is a quick reminder that the next Cologne R user group meeting is only one week away. We will meet on 6 July 2012. The meeting will kick off at 18:00 with three short talks at the Institute of Sociology and will continue, even more informal, from 20:00 in a pub (LUX) nearby.All details are available on the KölnRUG Meetup site. Please s...
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Applying a function successively in R
At the R in Finance conference Paul Teetor gave a fantastic talk about Fast(er) R Code. Paul mentioned the common higher-order function Reduce, which I hadn’t used before. Reduce allows me to apply a function successively over a vector. What does that mean? Well, if I would like to add up the figures 1 to 5, I could say: add <- function(x,y) x...
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Review: Kölner R Meeting 6 July 2012
The second Cologne R user meeting took place last Friday, 6 July 2012, at the Institute of Sociology. Thanks to Bernd Weiß, who provided the meeting room, we didn’t have to worry about the infrastructure, like we did at our first gathering. Again, we had an interesting mix of people turning up, with a very diverse background from chemistry to ...
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Bridget Riley exhibition in London
The other day I saw a fantastic exhibition of work by Bridget Riley. Karsten Schubert, who is Riley’s main agent, has a some of her most famous and influential artwork from 1960 – 1966 on display, including the seminal Moving Squares from 1961.Photo of Moving Squares by Bridget Riley, 1961Emulsion on board, 123.2 x 121.3cmIn the 1960s Bridget...
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London Olympics and a prediction for the 100m final
It is less than a week before the 2012 Olympic games will start in London. No surprise therefore that the papers are all over it, including a lot of data and statistis around the games. The Economist investigated the potential financial impact on sponsors (some benefits), tax payers (no benefits) and the athletes (if they are lucky) in its recent...
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Rook rocks! Example with googleVis
What is Rook?Rook is a web server interface for R, written by Jeffrey Horner, the author of rApache and brew. But unlike other web frameworks for R, such as brew, R.rsp (which I have used in the past1), Rserve, gWidgetWWWW or sumo (which I haven’t used yet) Rook appears incredible lightweight.Rook doesn’t need any configuration. It is an R pa...
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London Olympics 100m men’s sprint results
The 100m mean’s sprint finals of the 2012 London Olympics are over and Usain Bolt won the gold medal again with a winning time of 9.63s. Time to compare the result with my forecast of 9.68s, posted on 22 July. My simple log-linear model predicted a winning time of 9.68s with a prediction interval from 9.39s to 9.97s. Well, that is of course a...
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googleVis 0.2.17 is released: Displaying earth quake data
The next version of the googleVis package has been released on the project site and CRAN. This version provides updates to the package vignette and a new example for the gvisMerge function. The new sections of the vignette have been featured on this blog in more detail earlier: Using googleVis with knitr (Link to post) Using Rook with googleVis ...
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Sigma motion visual illusion in R
Michael Bach, who is a professor and vision scientist at the University of Freiburg, maintains a fascinating site about visual illusions. One visual illusion really surprised me: the sigma motion. The sigma motion displays a flickering figure of black and white columns. Actually it is just a chart, as displayed below, with the columns changing b...
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