Rather belatedly, I got around to posting a series of posts summarising the Formula One season to date: F1 2012 Mid-Season Review – Grid/Classification Analysis: for example, how do the drivers’ grid and final classifications compare? F1 2012 Mid-Season Review – Pit Stops: for example, how does pit stop performance across the teams ... [Read more...]

I have resisted learning the popular R graphics package, ggplot2. I dismissed ggplot2 as primarily useful for exploratory graphics and rationalized my avoidance of ggplot2 by assuming that it would require just as many (or more) lines of code as the R base package to whip the default plots into ... [Read more...]

By Earl F Glynn | Franklin Center A comparison of US Census voting age population data in Virginia to voter registration data shows only one locality, Surry County, with about 100% of the voting age population registered to vote. Six other localities have about 95% of their voting age population registered:  Craig County, ... [Read more...]

Context: I work with data from non-profit organizations, and so a big concern in many of my analyses is if and how much people are donating from one year to the next.  One of the  things I normally like to do … Continue reading → [Read more...]

You've probably heard (or seen in TV shows) how the unique pattern of rifling in a gunbarrel generates forensic evidence: microscopic scoring on the bullets left at the scene of the crime can be linked to the shooter by matching the marks to the firearm. What you might not know ... [Read more...]

After a sunny weekend to unpack and unwind, I am now back to my normal schedule, on my way to Paris-Dauphine for an R (second-chance) exam. Except for confusing my turn signal for my wiper, thanks to two weeks of intensive driving in four Australian states!, things are thus back ... [Read more...]

A proper introduction to the soilDB package is now available here. Installation and basic usage are covered. More detailed, task-specific documentation on aqp and soilDB will be available soon. read more [Read more...]

I’m sure that Carl Bacon[1] sighs deeply when he reads such headlines, but it is clearly appropriate in this case. Perhaps you remember that I proposed a Google Summer of Code project for 2012 around a considerable code contribution to PerformanceAnalytics from Diethelm Wuertz at ETHZ. That code was focused ... [Read more...]

We all know that it is important to plot your data and explore the data visually to make sure you understand it. The same is true for your model fits. First, you want to make sure that the model is fitting the data relatively well, without any substantial systematic deviations. ... [Read more...]

In my previous post I showed an animation of Arctic Sea Ice Extent from the 1980’s through August, 2012 (link).  In this post, I show how to build this Arctic Sea ice Extent  animated chart. Source Data The Arctic Ice … Continue reading → [Read more...]

I work in an environment dominated by SAS, and I am looking to integrate R into our environment. Why would I want to do such a thing? First, I do not want to get rid of SAS. That would not only take away most of our investment in SAS training ... [Read more...]

RStudio and knitr are an excellent conbination for generating dynamic reports. But in this blog, I will show you how to generate HTML-style presentaion using R only. OK, I confess that we still need something else: deck.js and markdown and R.utils. ... [Read more...]

R Packages All Well maintained? There are so many R packages, can they all be trusted? or are they well maintained? To answer this question, we just need to take a look of their archive histories. If a package has many versions, we can take that as th... [Read more...]

R Packages growth Curve Why R is so popular? There are a lot of reasons, such as: easy to learn and convenient to use, active community, open source, etc. Another important reason is the numerous contributed packages. Up to yesterday, there are 4033 R... [Read more...]

Most of regression methods assume that response variables follow some exponential distribution families, e.g. Guassian, Poisson, Gamma, etc. However, this assumption was frequently violated in real world by, for example, zero-inflated overdispersion problem. A number of methods were developed to deal with such problem, and among them, Quasi-Poisson and ... [Read more...]

After generating a few interactive charts with googleVis, I realized that it’s a great way to visualize numeric data, especially multi-dimentional data. Days ago, my colleague sent me a picture taken by Curiosity from Mars. He was crazy about it … Continue reading → [Read more...]

My coworkers at Fred Hutchinson regularly use the development version of R (i.e., R-devel) and have urged me to do the same. This post details how I have set up the development version of R on our Linux server, which I use remotely because it is much faster than ... [Read more...]

In our article How robust is logistic regression? we pointed out some basic yet deep limitations of the traditional full-step Newton-Raphson or Iteratively Reweighted Least Squares methods of solving logistic regression problems (such as in R‘s standard glm() implementation). In fact in the comments we exhibit a well posed ... [Read more...]

The Quick-and-Dirty Summary I was recently asked to participate in a proposed SXSW panel that will debate the question, “Will Data Scientists Be Replaced by Tools?” This post describes my current thinking on that question as a way of (1) convincing you to go vote for the panel’s inclusion in ... [Read more...]

Today Scott Chamberlain tweeted asking for a better/faster solution to building an m x n matrix with randomly assigned 0/1. He already had a working version: Now, I’m the first to acknowledge that I’ve never got the ‘apply’ family of … Continue reading → [Read more...]