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Hadley Wickham, the Rice professor and prolific R hacker best known as the author of the ggplot2 graphics package, will be coming to San Francisco June 8-9 to deliver his new R Development Master Class (in conjunction with Revolution Analytics). This course will build on the skills of basic R ... [Read more...]

Coercing variables of character and numeric type into a single dataframe yields all vectors to be defined as factors all [Read more...]

As part of my continuing fun and games getting to grips with ggplot2′s vast multitude of functions, here I give …Continue reading » [Read more...]

PDQ is a library of functions that helps you to express and solve performance questions about computer systems using the abstraction of queues. The queueing paradigm is a natural choice because, whether big (a web site) or small (a laptop), all computer systems can be represented as a network or ... [Read more...]

As I decided to try and blog a little more often now, and touch on "R" every now and then, I decided to take R-bloggers up on their standing offer to include R-related feeds at their site. So, everything I tag with "rstats" (you can guess where that ca... [Read more...]

Pete Warden's Data Science Toolkit (which we mentioned briefly last week) is an open-source information server that provides an API you can query for information useful for building data science applications, like identifying proper names in unstructured text, or converting IP addresses to lat/long coordinates. You can make queries ... [Read more...]

RStudio is a graphical user interface for R. Or as the developers put it. RStudio™ is a new integrated development environment (IDE) for R. RStudio combines an intuitive user interface with powerful coding tools to help you get the most out of R.   While there have been a few projects (... [Read more...]

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The FrF2 package for R can be used to create regular and non-regular Fractional Factorial 2-level designs. It is reasonably straightforward to use. First step is to install the package then make it available for use in the current session: require(FrF2) A basic call to the main functino FrF2 ... [Read more...]

This is a follow-up to a previous question on VRP. I investigated R libraries and several other options to solve VRP and decided to build a custom desktop application using open source libraries from COIN-OR. Screenshots attached below.Leave a comment ... [Read more...]

My thanks to those who emailed comments and suggestions for my ‘mfx’ function, I’m happy that I could fill a void for some people. I also received a request/suggestion from Tony Cookson, along with a helpful fix for a bug in the code, to include an option that ... [Read more...]

Last night I presented a talk at the DRUG introducing the R wrapper for the Data Science Toolkit.  Lots of good questions, good forking, and good beer afterwards at Freshcraft.  The slides are given below. [Read more...]

Two new local R user groups in Europe to announce this week. For R users in Serbia, there's a new group based in Belgrade. You can find more information about the group and upcoming meetings at the Croatian-language blog Sav tar R. And for R users in northern Italy, there's ... [Read more...]

The information below will be periodically updated at the folowing permanent link: http://www.backsidesmack.com/r-resources/ Searching for information on R sucks. Not only is the language name a letter of the alphabet (an ignominy it shares with C and some less well known languages), there is Pearson’s ... [Read more...]

Although this blog’s primary focus is time series, one feature I missed from Stata was the simple marginal effects command, ‘mfx compute’, for cross-sectional work, and I could not find an adequate replacement in R. To bridge this gap, I’ve written a (rather messy) R function to produce ... [Read more...]

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The 24 questions asked by John Halton in the conclusion of his 1970 survey are Can we obtain a theory of convergence for random variables taking values in Fréchet spaces? Can the study of Monte Carlo estimates in separable Fréchet spaces give a theory of global approximation? When sampling functions, ... [Read more...]

In the early stages of a literature review, you may have hundreds of papers and not know how to even begin sorting through them. In this post, I show you how to perform a two-stage clustering analysis with R so that you can identify the main groups within your data, ... [Read more...]

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