Andrew Little discusses two econometric packages developed by Gary King of Harvard, and how he has used them in his research at the August, 2009 NYC R Statistical Programming Meetup. Zelig - a single, easy-to-use package that can estimate, help inter... [Read more...]

I have just uploaded a bunch of new videos the Rchive (yea, that’s what I am calling it now). Most of the videos are from the April NYC meetup, which include the following talks: Pankaj Chopra—using R and Bioconductor (http://www.bioconductor.org/) for biomarker detection in cancer ... [Read more...]

Andrew Ilardi presents R project that analyzes a list of stocks to the NYC R Statistical Programming Meetup on April 8, 2010. Andrew's tool reaches out to the web to pull historical stock prices, then plots Quarter over Quarter correlations and a yea... [Read more...]

Pankaj Chopra discusses using R and Bioconductor (http://www.bioconductor.org/) for biomarker detection in cancer to the NYC R Statistical Programming Meetup on April 8, 2010. [Read more...]

Jared Lander discusses the science---and statistics---of finding the best pizza in NYC to the NYC R Statistical Programming Meetup on April 8, 2010. [Read more...]

In the following post, I describe how I've used the OOP features of R to create and use the following class hierarchy:Your browser does not support the element !/* generated with svg2canvas by Pierre Lindenbaum http://plindenbaum.blogspot.com [email protected] */function paint1271278100588(){var canvas=document.getElementById('ctx1271278100588... [Read more...]

Thanks to everyone who attended the webinar I presented this morning, High-Performance Analytics with REvolution R and Windows HPC Server. My slides are now available for download at the link below; even if you're not using Windows, I hope the slides are a useful introduction to the foreach parallel programming ... [Read more...]

How many observations should you have before constructing a confidence interval? [Read more...]

A friend just e-mailed me about a blog post by Dr. AnnMaria De Mars titled “The Next Big Thing”. In it Dr. De Mars wrote (I allowed myself to emphasize some parts of the text): Contrary to what some people seem to think, R is definitely not the next big ... [Read more...]

I have been meaning to look at adding some parallel processing to R as I have some scripts that are painfully slow and embarrassingly parallel. There seem to be a lot of packages around for doing parallel computing, listed here.I decided to look at mul... [Read more...]

William asks: How can I make a graph that looks like this, “tweet density” style, showing time intervals? He then helpfully describes his input data: a CSV file with headers “time started, time finished, date”. Here’s a simple CSV file, tasks.csv: task,date,start,end task1,2010-03-05,09:00:00,13:00:00 ... [Read more...]

It is not uncommon to see messy R code which is almost not human-readable like this: # rotation of the word "Animation" # in a loop; change the angle and color # step by step for (i in 1:360) { # redraw the plot again and again plot(1,ann=FALSE,type="n",axes=FALSE) # rotate; use ... [Read more...]

I recently did an analysis for the eMERGE network where I had lots of individuals from a small town in central Wisconsin where many of the subjects were related to one another. The subjects could not be treated as independent, but I could not use a fam... [Read more...]

Repeated measures ANOVA is a common task for the data analyst. There are (at least) two ways of performing “repeated measures ANOVA” using R but none is really trivial, and each way has it’s own complication/pitfalls (explanation/solution to which I was usually able to find through searching ... [Read more...]

In a prior article, I tried to visualize the linear global temperatures trends for a grid of start and end years. The visual I created was confusing in that the specification of color scale was interdependent with the data values. I wanted a blue -__ white -__ red scale of ... [Read more...]

Setting up Eclipse to use MKL-Linked RIn my previous post, I showed how to compile R 2.10.1 using Intel's Math Kernel Library for the BLAS/LAPACK interface. Even though it takes a bit of time to setup, I think the noticeably improved calculation speed justifies the effort. Although I'm happy to ... [Read more...]

Good news. Jeroen Ooms released a new version of his (amazing) online ggplot2 web interface: yeroon.net/ggplot2 is a web interface for Hadley Wickham’s R package ggplot2. It is used as a tool for rapid prototyping, exploratory graphical analysis and education of statistics and R. The interface is ... [Read more...]

Version 1.0.5 is now on CRAN. This version brings some bug fixes as well as two new features: Unlabeled code chunks are now allowed. The correct version of PGF is now checked for on startup. If the version is __ 2.00, the package will fail to load.... [Read more...]

A court in Arizona has ruled that statistical sampling is legal for determining damages awarded to individual claimants when there are thousands of similar cases to be assessed simultaneously. In a case where 30,000 claims were filed Maricopa County, AZ by hospitals for improper reimbursement, the trial judge appointed a former ... [Read more...]

The Trellis graphics approach provides facilities for creating effective graphs with a consistent look and feel and one of the good things about the system is the use of themes to define the colour, size and other features of the components that make up a graph. The lattice package in ... [Read more...]