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One of the great things that I am learning about R is that it is really powerful as a data management tool.  I just found how to unzip files.  I could use Python for this in SPSS, but it just feels like it is more natural to do in R.  ... [Read more...]

Birds do it, bees do it. But the bees and their insect brethren definitely do it in a more interesting way. Don't believe me? Check out Isabella Rosselini's description of bee sex and the other videos in her educational "Green Porno" series. It's fascinating stuff. For some light summer reading, ... [Read more...]

There's been a lot of talk about the slicks and plumes of oil from the Deepwater Horizon disaster, but how does the presence of that oil translate into measurable pollution in the air, water, and sediment? The EPA is now releasing pollutants and making the data available for analysis. Because ... [Read more...]

I really like R‘s stem function, it creates a stem-and-leaf plot right in the R console, no fancy graphics devices required! In a recent R-help post, Ralf Bierig presented a very nice ASCII scatterplot representing two densities. Unfortunately, I don’t know of any R function that will generate ... [Read more...]

Two way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models ... [Read more...]

One way analysis of variance models can be fitted to data using the R Commander GUI. The general approach is similar to fitting the other types of model in R Commander described in previous posts. Fast Tube by Casper The “Statistics” menu provides access to some analysis of variance models ... [Read more...]

A new R user group has launched in Sydney. It aims to bring together both experienced R users and complete beginners. The forum will meet monthly with talks on a wide range of subjects exploring all of the facets of this powerful tool. [Read more...]

Edit: And here is an update of the update, this one contributed by Kai Heinrich. Here’s an updated version of my script from last month, something I’ve been meaning to do for a while. I thank Anatol Stefanowitsch and Gábor Csárdi for improving my quite sloppy ... [Read more...]

In the Introduction to his book “R for SAS and SPSS Users” (Springer 2009) Robert Muenchen offers ten reasons for learning R if you already know SAS or SPSS. All ten reasons say something important about R. However, his fourth reason: “R’s language is more powerful than SAS or SPSS. ... [Read more...]

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We can use the R Commander GUI to fit logistic regression models with one or more explanatory variables. There are also facilities to plot data and consider model diagnostics. The same series of menus as for linear models are used to fit a logistic regression model. Fast Tube by Casper ... [Read more...]

Revolution Analytics is proud to sponsor the New York R User Group. The last meeting was on the theme of debugging in R, and some videos of the talks are now available at the Video Rchive. Jay Emerson have a talk on Basic debugging in R and Harlan Harris dived ... [Read more...]

I ran a across a strange bug in R recently. Like all the best programming languages, R treats functions as first class objects. That is to say that functions can be passed as arguments and return values from functions, named as variables, and, while not part of the strict definition ... [Read more...]

Here is a scatter plot with the coordinate labels deliberately omitted. Figure 1. Do you see any trends? How would you model these data? It just so happens that this scatterplot is arguably the most famous scatterplot in history. One aficionado, writing more than forty years after its publication, commented skeptically [1]:"[... [Read more...]

Sample once from the Uniform(0,1) distribution. Call the resulting value . Multiply this result by some constant . Repeat the process, this time sampling from Uniform(0, ). What happens when the multiplier is 2? How big does the multiplier have to be to force divergence. Try it and see: iters = 200 locations = rep(0,iters) [...] [Read more...]

Here's another great example of R being used to analyze sports data. Statistician and skier Joran Elias has started a project to analyze and visualize international cross country ski racing results, and he publishes his analysis at the blog Statistical Skier. All of the analyses are done using R (and ... [Read more...]

We have a mild obsession with employee productivity and how that declines as companies get bigger. We have previously found that when you treble the number of workers, you halve their individual productivity which is mildly scary. We revisit the analysis for the FTSE-100 constituent companies and find that the ... [Read more...]

The top six most violent municipalities are near the US border. Ciudad Juárez is in a class by itself with 113 homicides per 100,000 people. José Azueta is the municipality where Zihuatanejo is located. Mazátlan, another popular tourist destination, also appears on the list.  Lázaro Cárdenas is the ... [Read more...]

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