multiplicitiesoffreedom demonstrates Chaos Theory in Excel. If he filled in more initial values, you would see a thick bar—like a picture of white-noise. Butterflies flapping their wings in Vermont to change the wind in Hangzhou? A drop of water on ... [Read more...]

Preface. This is the first of what I hope will be many posts analysing experimental data, that will eventually end up in my empirical software engineering with R book (this experiment was chosen because it happens to be the one I am currently working on; having just switched to using ... [Read more...]

R''s glm function for generalized linear modeling is very powerful and flexible: it supports all of the standard model types (binomial/logistic, Gamma, Poisson, etc.) and in fact you can fit any distribution in the exponential family (with the family argument). But if you want to use it on a ... [Read more...]

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By now you've probably heard about the fact that Orbitz users accessing the site via Macs are seeing more expensive hotel options when they search. But it seems worth clearing up a couple of fallacies. First, it's not as if the same hotel room is being offered at a higher ... [Read more...]

This article gives a brief overview of the data.table package written by M. Dowle, T. Short, S. Lianoglou. A data.table is an extension of a data.frame created to reduce the working time of the user in two ways programming time … Continue reading → [Read more...]

I want to continue with Factor Attribution theme that I presented in the Factor Attribution post. I have re-organized the code logic into the following 4 functions: factor.rolling.regression – Factor Attribution over given rolling window factor.rolling.regression.detail.plot – detail time-series plot and histogram for each factor factor.rolling.... [Read more...]

While the US's Major League Soccer is using advanced analytics to analyze ball movement and improve team composition, they might want to think about a smaller, but possibly more impactful, goal for analytics. Like, how to explain to an American audience what a 1-2 game means to a basketball or ... [Read more...]

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When I am working in new institutions and I am asking: “Do you have a document management system?” I often get the answer:”Yap, we are using folders” … OKAY. Making analysis, developing applications and keeping an eye on code, data and applications make this even harder as it has to ... [Read more...]

Following the Irish rugby team’s humiliating 60-0 defeat to New Zealand, an interesting question was posed on Twitter: what does a 60-0 result convert to in football/soccer? Intrigued, I decided to gather some data from both the English premier league (this season, more data collected and future blog ... [Read more...]

Two new local R user groups to report this week. In Turkey, the Ankara R Users Group has just started up. No meetings are scheduled yet, so be sure to suggest a meeting time/location when you sign up. The Toronto-based R Matlab Users group focuses on financial services applications. ... [Read more...]

As promised. Looks like a Spain Germany final. [Read more...]

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I like statistics and I struggle with statistics. Often times I get frustrated when I don’t understand and I really struggled to make sense of Krushke’s Bayesian analysis of a split-plot, particularly because ‘it didn’t look like’ a split-plot to … Continue reading → [Read more...]

If I would like to adjust a shape file I normally used the way over an excel file or a text file to get a table and to join this with an existing shape file. Due to the sp and rgdal packages in R you can manipulate shapefiles directly in ... [Read more...]

It’s gutted that I could not attend useR! 2012 after having a great time at useR!2011 at Warwick. However, a great active online community of useRs allows me to get lots of goods stuffs from the conference even though I did not attend physically. By keep following the #useR2012 and #... [Read more...]

Most of us R users are using a special working directory for the daily work in R. But I was bothered in typing everytime in my command line prior using R. Also using this line at the first position in scripts was not pleasent enough. So how to get around ... [Read more...]

I will be giving a short course in Switzerland next week, at the 6th R/Rmetrics Meielisalp Workshop & Summer School on Computational Finance and Financial Engineering organized by ETH Zürich, https://www.rmetrics.org/. The long... [Read more...]