Blog Archives

London Olympics 100m men’s sprint results

August 5, 2012
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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 ...

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Rook rocks! Example with googleVis

August 1, 2012
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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...

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London Olympics and a prediction for the 100m final

July 22, 2012
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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 spons...

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Bridget Riley exhibition in London

July 11, 2012
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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...

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Review: Kölner R Meeting 6 July 2012

July 10, 2012
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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 ...

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Applying a function successively in R

July 3, 2012
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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...

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Reminder: Next Kölner R User Meeting 6 July 2012

June 27, 2012
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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, ...

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Hodgkin-Huxley model in R

June 24, 2012
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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...

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Dynamical systems in R with simecol

June 18, 2012
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Dynamical systems in R with simecol

This evening I will talk about Dynamical systems in R with simecol at the LondonR meeting. Thanks to the work by Thomas Petzoldt, Karsten Rinke, Karline Soetaert and R. Woodrow Setzer it is really straight forward to model and analyse dynamical systems...

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Transforming subsets of data in R with by, ddply and data.table

June 11, 2012
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Transforming subsets of data in R with by, ddply and data.table

Transforming data sets with R is usually the starting point of my data analysis work. Here is a scenario which comes up from time to time: transform subsets of a data frame, based on context given in one or a combination of columns.As an example I use ...

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