Monthly Archives: May 2010

Mixed linear model approach adapted for genome-wide association studies

May 6, 2010
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A few weeks ago I covered an R package for efficient mixed model regression that is capable of simultaneously accounting for both population stratification and relatedness to compute unbiased estimates of standard errors and p-values for genetic associ...

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Rearranging definitions in R

May 6, 2010
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Rearranging definitions in R

I came up with a handy little trick for programming in R. I like to define a lot of variables all at once without worrying about what order they’re in. The goal would be something like this: K  = -R2/R1 … Continue reading →

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Candy branching process

May 5, 2010
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Candy branching process

The mathematical puzzle in the latest weekend edition of Le Monde is as follows: Two kids are given three boxes of chocolates with a total of 32 pieces. Rather than sharing evenly, they play the following game: Each in turn, they pick one of the three boxes, empty its contents in a jar and pick

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Game of Life in R

May 5, 2010
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Game of Life in R

Before I decided to learn R in a serious way, I thought about learning Flash/Actionscript instead. Most of my work involves evolutionary models that take place over time. I need visual representations of change. It’s certainly possible to represent change and tell an evolving story with a single plot (see for example Tufte’s favorite infographic),

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13 videos for learning R

May 5, 2010
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Jeromy Anglim has just posted a nice round-up of instructional videos for learning R. The videos are categorized into four levels: What is R? Introductory R? Intermediate and Advanced Materials on R and Related Resources (including a link to written resources for getting started with R). Check out all the links at Jeromy's post, linked below. Jeromy Anglim's blog:...

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Fun with R: Clustering and MDS

May 5, 2010
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Fun with R: Clustering and MDS

I've seen K-means clustering, PCA, etc. done some over at Beyond the Boxscore and Baseball Analysts (and the now defunct Statspeak), but I thought I'd just check out some clustering on the young fantasy season using the traditional 5x5 categories with ...

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Videos on Data Analysis with R: Introductory, Intermediate, and Advanced Resources

May 4, 2010
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If you want to learn about R through videos, there are now a large number of options. This post provides links to many of these video under the headings of: (a) What is R? (b) Introductory R, and (c) Intermediate and Advanced R. What is R?If you are...

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Videos on Data Analysis with R: Introductory, Intermediate, and Advanced Resources

May 4, 2010
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Videos on Data Analysis with R: Introductory, Intermediate, and Advanced Resources

If you want to learn about R through videos, there are now a large number of options.This post provides links to many of these video under the headings of:(a) What is R?(b) Introductory R, and(c) Intermediate and Advanced R.What is R?If you are evaluat...

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You won, but how much was luck and how much was skill?

May 4, 2010
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You won, but how much was luck and how much was skill?

In baseball, what are the chances the winner will win again against the same opponent the very next day?

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Modifying basic plots in R

May 4, 2010
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Below is a walk-through of some of the basics of customizing plot in R. These are all based on the graphics package that comes in the base installation of R. Let’s start by making a basic plot in R. In the code snippets below, green text behind a...

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