R Tutorial Series: Labeling Data Points on a Plot

September 19, 2010
By
R Tutorial Series: Labeling Data Points on a Plot

There are times that labeling a plot's data points can be very useful, such as when conveying information in certain visuals or looking for patterns in our data. Fortunately, labeling the individual data points on a plot is a relatively simple process ...

Read more »

R Tutorial Series: Labeling Data Points on a Plot

September 19, 2010
By
R Tutorial Series: Labeling Data Points on a Plot

There are times that labeling a plot's data points can be very useful, such as when conveying information in certain visuals or looking for patterns in our data. Fortunately, labeling the individual data points on a plot is a relatively simple process ...

Read more »

Why Use ProjectTemplate or Any Other Framework?

September 19, 2010
By

We use frameworks like Ruby on Rails or ProjectTemplate to minimize the time we spend on irrelevant details. By definition, an irrelevant detail isn’t of interest to us. But how can we tell which details are irrelevant? This isn’t a trivial task and it seems to be, on the surface, a profoundly subjective matter. Thankfully,

Read more »

Response Times, The Exponential Distribution and Poisson Processes

September 18, 2010
By
Response Times, The Exponential Distribution and Poisson Processes

I’m currently reading Luce’s “Response Times”. If you don’t know anything about response times, they are very easily defined: a response time is the length of time it takes a person to respond to a simple request, measured from the moment when the request is made to the moment when the person’s response is recorded.

Read more »

Elder Research Two Day Course

September 18, 2010
By

... or what I did on my summer vacation...Just got back from the Elder Research Two Day Course "Tools for Discovering Patterns in Data".  It was a great course that (while not R specific) provides a great overview of Data Mining tools and tec...

Read more »

Elder Research Two Day Course

September 18, 2010
By

... or what I did on my summer vacation...Just got back from the Elder Research Two Day Course "Tools for Discovering Patterns in Data".  It was a great course that (while not R specific) provides a great overview of Data Mining tools and tec...

Read more »

Using R

September 18, 2010
By
Using R

By Matt BogardAbstractR is a statistical programming language with a command line interface that is becoming more and more popular every day. I have used R for data visualization, data mining/machine learning, as well as social network analysis. Initia...

Read more »

Classification Trees

September 18, 2010
By
Classification Trees

Decision trees are applied to situation where data is divided into groups rather than investigating a numerical response and its relationship to a set of descriptor variables. There are various implementations of classification trees in R and the some commonly used functions are rpart and tree. Fast Tube by Casper To illustrate the use of the tree

Read more »

What should we call the stats Q&A site?

September 18, 2010
By
What should we call the stats Q&A site?

The Q&A site at stats.stackexchange.com has been steaming ahead with loads of good questions and answers. We are currently trying to select a name and not many people have voted. Although we have more than 1300 users of the site, less than 40 people have currently voted on the name. There are four days left.

Read more »

A simple Metropolis-Hastings MCMC in R

September 17, 2010
By
A simple Metropolis-Hastings MCMC in R

While there are certainly good software packages out there to do the job for you, notably BUGS or JAGS, it is instructive to program a simple MCMC yourself. In this post, I give an educational example of the Bayesian equivalent of a linear regression, sampled by an MCMC with Metropolis-Hastings steps, based on an earlier…

Read more »

Running R on the iPad

September 17, 2010
By

I'm a hardcore Mac user, so it's annoying to me that we don't yet support Revolution R Enterprise on MacOS X. Believe me, I've argued the point. But MacOS is still a relatively uncommon platform in business, and there's just not the demand yet from customers to justify porting the Revolution R extensions to MacOS X. (Open-source Revolution R...

Read more »

Installing ‘intergraph’ package

September 17, 2010
By
Installing ‘intergraph’ package

After some e-mails I decided to put together a bit more detailed instruction how to install the ‘intergraph’ package together with the namespaced version of the ‘network’ package. See here. There seemed to be some problems with downloading the namespaced ‘network’ from my webstite (thanks Neil!). File permissions were set incorrectly. I fixed that and

Read more »

Physical economy v social economy

September 17, 2010
By
Physical economy v social economy

There’s a hole in the bucket of traditional economics. Homo socialus seems to be on the rise, and homo economicus is getting harder to find. Vulcanism has become evident in the R community over the last several days.  One of the visible eruptions has been over money.  This resulted in a blog post by Tal … Continue reading...

Read more »

Typo in Example 3.6

September 16, 2010
By
Typo in Example 3.6

Edward Kao pointed out the following difficulty about Example 3.6 in Chapter 3 of “Introducing Monte Carlo Methods with R”: I have two questions that have puzzled me for a while. I hope you can shed some lights. They are all about Example 3.6 of your book. 1. On page 74, there is a term

Read more »

Open source and money – why paying R developers might not always help the project

September 16, 2010
By

This post can be summed up by one two sentences: “We can’t buy love.” “Starting to pay for love could make it disappear” while at the same time “We need money to live and love”. These two conflicting forces, with relation to open source, are the topic of this post. This post is directed to the community or R...

Read more »

Complex-valued linear models

September 16, 2010
By
Complex-valued linear models

Someone has probably already written code to do this. But I couldn’t find it in CRAN, so here goes. Oh no lm() won’t take complex numbers! (or rather, it’ll take them, but it’ll discard the imaginary part.) Easy enough fix. … Continue reading →

Read more »

R’s time is now

September 16, 2010
By

Jeff Kelly of Tech Target has just published a feature article about R. While R has been around for almost 20 years now (R&R first started the project in 1993), "its time may have finally come", he says. One thing I really like about the article is how well it highlights R's flexibility and "top-notch" data visualizations. It includes...

Read more »

Did what you write drive what I read?

September 16, 2010
By
Did what you write drive what I read?

GoogleReader allows you to track your activity, by representing the number of news items read and published by day and by hour. I use it quite a lot to stay up to date with the scientific literature (I subscribed to probably over 30 journals) and a bunch of other feeds. Stuff tend to accumulate faster

Read more »

Principal Component Analysis (PCA) vs Ordinary Least Squares (OLS): A Visual Explanation

September 16, 2010
By
Principal Component Analysis (PCA) vs Ordinary Least Squares (OLS): A Visual Explanation

Over at stats.stackexchange.com recently, a really interesting question was raised about principal component analysis (PCA). The gist was “Thanks to my college class I can do the math, but what does it MEAN?” I felt like this a number of times in my life. Many of my classes were focused on the technical implementations they kinda

Read more »

BLAS, BLASter, BLAStest: Some benchmark results, and a benchmarking framework

September 15, 2010
By
BLAS, BLASter, BLAStest: Some benchmark results, and a benchmarking framework

Usage of accelerated BLAS libraries seems to shrouded in some mystery, judging from somewhat regularly recurring requests for help on lists such as r-sig-hpc (gmane version), the R list dedicated to High-Performance Computing. Yet it doesn't have to be...

Read more »

BLAS, BLASter, BLAStest: Some benchmark results, and a benchmarking framework

September 15, 2010
By
BLAS, BLASter, BLAStest: Some benchmark results, and a benchmarking framework

Usage of accelerated BLAS libraries seems to shrouded in some mystery, judging from somewhat regularly recurring requests for help on lists such as r-sig-hpc (gmane version), the R list dedicated to High-Performance Computing. Yet it doesn't have to b...

Read more »

Dumping functions from the global environment into an R script file

September 15, 2010
By

Looking at a project you didn’t touch for years poses many challenges. The less documentation and organization you had in your files, the more time you’ll have to spend tracing back what you did back when the code was written. I just opened up such a project, that was before I ever knew to split my .r files to...

Read more »

Three dimensional plots using rgl package

September 15, 2010
By
Three dimensional plots using rgl package

We all know that R can do amazing things including 3 dimensional plots. scatterplot3d is probably the most popular package for doing this. But a few days ago I got introduced with rgl package which can do 3 dimensional graphs with some added advantages like we can rotate the plot using mouse, zoom in or out using the mouse...

Read more »

Three dimensional plots using rgl package

September 15, 2010
By
Three dimensional plots using rgl package

We all know that R can do amazing things including 3 dimensional plots. scatterplot3d is probably the most popular package for doing this. But a few days ago I got introduced with rgl package which can do 3 dimensional graphs with some added advantages like we can rotate the plot using mouse, zoom in or out using the mouse...

Read more »

New R User Group in Brisbane

September 15, 2010
By

There are now four -- count 'em, four -- local R user groups in Australia, with the addition of the latest group in Brisbane, Queensland. GRUB (Group for R Users in Brisbane) is just getting started and doesn't have a meeting scheduled yet, but if you're in the vicinity why not join up and make a suggestion! meetup.com: Group...

Read more »

R Function Reference

September 15, 2010
By
R Function Reference

The R Function Reference is a mind map that I've created to help novice and intermediate R users perform common tasks and analyses.

Read more »

Who’s the best all rounder in World Cup Cricket history?

September 14, 2010
By
Who’s the best all rounder in World Cup Cricket history?

We love cricket all rounders (players who can both bat and bowl). These players are great assets for their teams and captains love 'em. So, who are the best all rounders in World Cup Cricket history?Kapil, Steve Waugh and Jayasuriya have all performed ...

Read more »

Who’s the best bowler in World Cup Cricket history?

September 14, 2010
By
Who’s the best bowler in World Cup Cricket history?

We've witnessed many great bowlers in World Cup Cricket - Shane Warne and Murlidharan, the spin wizards, and Wasim Akram and Waqar Younis, the toe-breakers. However, the data indicates that the marathon man, the-run-up-and-bowl-accurately guy, Glen McG...

Read more »

Who’s the best batsman in World Cup Cricket history?

September 14, 2010
By
Who’s the best batsman in World Cup Cricket history?

There have been many debates on identifying the best batsman in World Cup Cricket. Here's one way to determine it. The data shows Sachin Tendulkar as the best ever based on total runs scored (large bubble size), strike rate and runs/game. Bow to the ma...

Read more »