As usual, the Guerrilla Data Analysis Techniques (GDAT) class was a total blast. Motivated students always guarantee that. It would really help our scheduling, however, if people didn't wait until the last nanosecond to register for the class. But give... [Read more...]

See also: Part 1: QTL Analysis and Quantitative Genetics  Part 2: Statistical Methods for QTL Analysis The 'qtl' package in R allows you to implement QTL analysis using the methods I've previously discussed. The code below is adapted from Broman... [Read more...]

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In my last post I talked about using the number of lines in a function as a guide to whether you need to break it down into smaller pieces. There are many other useful metrics for the complexity of a function, most notably cyclomatic complexity, which tracks the number of ... [Read more...]

Because it’s Friday—and I needed to create this for a separate visualization—here is how to create an animated clock in R using ggplot2. In just about 20 lines of code! And here is the clock… I think this is a nifty way to show time elapse, rather than ... [Read more...]

The most recent edition of the Revolution Newsletter is out. The news section is below, and you read the full August edition (with highlights from this blog and community events) online. You can subscribe to the Revolution Newsletter to get it monthly via email. Free 30-minute introduction to Revolution R ... [Read more...]

Tweet When I first started using R, one of the things that attracted me was its claim to be an object-oriented programming (OOP) language. Coming from a Java background, I was used to designing software with OOP concepts like encapsulation and inheritance but, when I turned my hand to R, ... [Read more...]

Some may have already noticed that the last post appeared on the R-bloggers.com, but here now is the official announcement. R-bloggers.com aggregates blogs which write about R. Since questions about R constitute roughly 20% of all the questions on CrossValidated, it is natural that the community blog of CrossValidated ... [Read more...]

It’s widely considered good programming practice to have lots of little functions rather than a few big functions. The reasons behind this are simple. When your program breaks, it’s much nicer to debug a five line function than a five hundred line function. Additionally, by breaking up your ... [Read more...]

I’ve been thinking a lot about what it means for two variables to be correlated.  Scientists throw around the term like it’s uniformly understood, but I fear that an understanding of the concept is elusive to substantive researchers who aren’t interested in empirical methods, except as a ... [Read more...]

The patch release, 3.1.0  fixes a problem due to a change in the way the adapt command works (and the adapt() function in rjags).  If the model has an adaptive phase, you should normally include a burn in period (with … Continue reading → [Read more...]

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Additive genetic covariance between individuals is one of the key concepts in (quantitative) genetics. When doing the prediction of additive genetic values for pedigree members, we need the inverse of the so called numerator relationship matr... [Read more...]

An article in FastCompany today profiles two websites that excel in telling engaging stories with data: the FlowingData and OkTrends blogs. Both sites often use R for data analysis and data visualization, and have been featured here on this blog. FlowingData regularly posts guides on how to use R to ... [Read more...]

Thursday 11 August 2011 - 22:36 OpenAnalytics is happy to sponsor UseR!2011 and will present recent work that has been released under open source license in three presentations: R and GPU Computing, which accompanies the first public release of... [Read more...]

Very often scientists are worried about performance and security in cloud computing. Especially, when talking about High-Performance Computing (HPC) in the cloud it is a very important aspect to proof efficient calculation speed in the cloud. Cloud computing describes a new delivery model for IT services based on Internet protocols, ... [Read more...]

What is OpenMP? Basically a standard compiler extension allowing one to easily distribute calculations over multiple processors in a shared-memory manner (this is especially important when dealing with large data — simple separate-process approach usually requires as many copies of the working data as there are threads, and this may easily ... [Read more...]

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In a time series, I want to plot the values of an interesting cluster versus the background. However, if I'm not careful, ggplot will draw the items in an order determined by their name, so background items will obscure the interesting cluster: Corr... [Read more...]

I have the 64 bit version of R compiled from source on my Ubuntu laptop. I recently had a need for R based on 32 bit since a package I needed to compile and use only works in 32 bit. I thought it was readily available on Ubuntu since both 32 bit and 64 bit... ... [Read more...]