With the election nearly upon us, I wanted to share an easy way I just found to download polling data and graph a few with ggplot2. dlinzer at github created a function to download poll data from the Huffington Post's Pollster API.The default is to dow... [Read more...]

In response to last week's post on the rapidly increasing ideology of the US Republican Party, Mike Lawrence suggested another way of looking at the DW-NOMINATE ideology data. Rather than simply looking at boxplots of the congress scores by party over time, we could fit a smooth curve to get ... [Read more...]

A new version 0.2.9 of RInside arrived on CRAN earlier today; Windows binaries have already been built too. RInside provides a set of convenience classes which facilitate embedding of R inside of C++ applications and programs, using the classes and ... [Read more...]

The purpose of Rcpp modules has always been to make it easy to expose C++ functions and classes to R. Up to now, Rcpp modules did not have a way to declare inheritance between C++ classes. This is now fixed in the development version, and t... [Read more...]

In this post I showed a visualization of the organizational network of my department. Since several people asked for details how the plot has been produced, I will provide the code and some extensions below. The plot has been done … Continue reading → [Read more...]

When I talk about collaborative work, I don’t mean spending a day or two helping compute some p-values and end up as middle author in a subject-matter paper. I mean spending months working on a project, from start to finish, with experts … Continue reading → [Read more...]

  Much of my time lately has gone into analyzing and trading products in the volatility complex.  As a result, I regularly watch the VIX term structure for continuations or deviations from trend.  To make analysis simpler, I’ve written some… Read more › [Read more...]

Dear R experts, I sent this question to the r-help list but didn’t get much response, probably because it is more of a stats question. But as this blog is syndicated on r-bloggers I thought I would try it again here on this blog. If I am barking up ... [Read more...]

This post is a little more esoteric than most, but I found myself needing to solve this problem, so I’m just passing the solution on to you. The plot above shows the distribution of DW-NOMINATE scores for the 18th Congress, with party indicated ... [Read more...]

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Here’s an addition to my last post on using Wikipedia data to analyse attention for the US presidential elections 2012. Here’s another look at the interest not for the candidates’ Wikipedia pages but the general pages for the elections 2008 and 2012. Compared to the candidates’ pages, the attention for the ... [Read more...]

  In this post I like to illustrate the R package “ape” for phylogenetic trees for the purpose of assembling trees. The function read.tree creates a tree from a text description. For example the following code creates and displays two … Continue reading → [Read more...]

For now this is the last post about these football data. It started in August, by now it is November. But just to finish up; the model as it should have been last week.ModelAs most of what I did is described last week, only the model as it went ... [Read more...]

Brian Caffo headlines the WaPo article about massive online open courses. He is the driving force behind our department’s involvement in offering these massive courses. I think this sums it up: `“I can’t use another word than unbelievable,” Caffo said. … Continue reading → [Read more...]

Plotting large amounts of hourly atmospheric data body, td { font-family: sans-serif; background-color: white; font-size: 12px; margin: 8px; } tt, code, pre { font-family: 'DejaVu Sans Mono', 'Droid Sans Mono', 'Lucida Console',... [Read more...]

One of the most interesting challenges of data science are predictions for important events such as national elections. With all those data streams of billions of posts, comments, likes, clicks etc. there should be a way to identify the most important correlations to make predictions about real-world behavior such as: ... [Read more...]

My previous post is about a method to simulate a Brownian motion. A friend of mine emailed me yesterday to tell me that this is useless if we do not know how to simulate a normally distributed variable. My first remark is: use the rnorm() function if t... [Read more...]

A few days ago a post doctoral researcher asked me if I could help him reorder the factor levels on a bar chart. The problem is that R automatically alphabetizes factor levels. I thought this would be fairly straight-forward but... [Read more...]

It’s been over one month since my last post on Euler problem 20, when  I was planning to post at least one on either Euler project or visualization. So I am four posts behind; I’ll try to catch up. Tonight, I’ll solve the 21st Euler … Continue reading → [Read more...]

A real developer never stops learning that's a quote I always love to repeat...because it applies to my life...you can know a lot of things but there's always something new to learn, or to re-learn. That's why a couple of days ago I start reading wxPyt... [Read more...]