Publications by David Smith

How to call C++ from R with ease

19.02.2010

At last night’s meeting of the ACM Student Chapter at the University of Chicago, DIrk Eddelbuettel gave an invited guest lecture, “Programming with Data: Using and Extending R”. I wasn’t there myself, but Dirk has already posted his slides, and they’re a treat. After a backgrounder on R itself (BTW, I’m flattered he referenced my Intr...

1335 sym

Where did all the bankers go?

19.02.2010

When Lehman Brothers, Bear Stearns and Merrill Lynch went kablooie in the financial crisis, what happened to all their employees? Thanks to the magic of LinkedIn data, their Chief Scientist DJ Patil can answer that question: they went to the surviving banks:  It’s a great, if tantalizingly incomplete visualization — I’d love to see this wi...

958 sym 2 img

Speeding up R code: A case study

22.02.2010

On his Psychology and Statistics blog, Jeromy Anglim tells how he was analyzing some data from a skill acquisition experiment. Needing to run a custom R function across 1.3 million data points, Jeromy estimated it would take several hours for the computation to complete. So, Jeromy set out to optimise the code.First, he used the Rprof function, w...

2042 sym

Slides from “R Productivity Environment” webinar

23.02.2010

Thanks to everyone who attended for the great turnout at this morning’s live webinar, 7 Ways to Increase your R Productivity. I really appreciate all the feedback and questions, seems like a lot of people are interested in a code editing and debugging environment for R. If you missed the webinar and want to learn about REvolution R Enterprise ...

934 sym

Reminder: useR! 2010 abstracts due Monday

23.02.2010

Don’t forget, if you’re planning to attend the R user conference useR! 2010 and are going to present a talk (and if not, why not?), abstracts are due for submission this coming Monday, March 1. That’s also the deadline for early-bird registrations, so if you haven’t registered yet, now is the time.useR! 2010: The R User Conference Relate...

726 sym

Object types in R: The fundamentals

24.02.2010

If you’re a self-taught R programmer, you’ve probably grappled with the different kinds of objects you can use in the language. When should you use a list instead of a vector? What’s the difference between a factor and character vector? These questions are easier to answer when you have some of the basics of R’s object types down pat, a...

1559 sym

Solving Sudoku with Simulated Annealing

25.02.2010

How long would it take you to solve this devlishly hard Sudoku puzzle (from Le Monde)? You could do it the old-fashioned way — with a pencil — but Xi’an decided to solve it by programming a simulated annealing solver in R. The algorithm works by first guessing a solution at random — filling in the empty cells above with random digits be...

1262 sym 2 img

Because it’s Friday: Visualizing an email chain

26.02.2010

We’ve all been there: someone sends an email to a mailing list with a Reply-To directing responses back to the mailing list. Before long, someone replies (unwittingly, to everyone) to ask to be taken of the list. And before long, the entire affair devolves into an endless cycle of requests to unsubscribe and pleas to stop mailing the entire lis...

1075 sym 2 img

Steve Miller on R at Predictive Analytics World

26.02.2010

At the Information Management blog, Steve Miller has provided two great reviews (here and here) of last week’s Predictive Analytics World conference, including a recap of the Bay Area User’s Group meeting featuring John Chambers. (My personal highlight from John’s talk? A photograph of the very first sketch of what was to become the S syste...

3065 sym

REvolution Computing hiring parallel computing developer

01.03.2010

We’re looking for a programmer with experience in high-performance computing and the R system to work on the ParallelR suite and other data-analysis projects. Sound like anyone you know? Check out the details at the link below.REvolution Computing careers: Parallel Computing Developer Related To leave a comment for the author, please follow...

679 sym