Monthly Archives: May 2013

Writing a Minimal Working Example (MWE) in R

May 27, 2013
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Writing a Minimal Working Example (MWE) in R

How to Ask for Help using R How to Ask for Help using R The key to getting good help with an R problem is to provide a minimally working reproducible example (MWRE). Making an MWRE is really easy with R, and it will help ensure that...

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Bayesian model II regression

May 27, 2013
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Bayesian model II regression

Regression is a mainstay of ecological and evolutionary data analysis. For example, a disease ecologist may use body size (e.g. a weight from a scale with measurement error) to predict infection. Classical linear regression assumes no error in covariates; they are known exactly. This is rarely the case in ecology, and ignoring error in covariates can bias regression coefficient...

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(Another) introduction to R

May 27, 2013
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(Another) introduction to R

It’s Memorial Day and my dissertation defense is tomorrow. This week I’m phoning in my blog. I had the opportunity to teach a short course last week that was part of a larger workshop focused on ecosystem restoration. A fellow grad student and I taught a session on Excel and R for basic data analysis.

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useR! 2013 conference update

May 27, 2013
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Been trying to reach the website for the useR! 2013, the R user conference that will be held July 10-12 2013 at University of Castilla-La Mancha in Spain? There have been some server problems recently, but you can now get access at the official URL, www.r-project.org/useR-2013/. If you're going, be sure to check out the newly-announced Data Analysis Contest,...

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Log Transformations for Skewed and Wide Distributions

May 27, 2013
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Log Transformations for Skewed and Wide Distributions

This is a guest article by Nina Zumel and John Mount, authors of the new book Practical Data Science with R. For readers of this blog, there is a 50% discount off the “Practical Data Science with R” book, simply by using the code pdswrblo when reaching checkout (until …Read more »

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Combinatorial optimization with gaoptim package

May 27, 2013
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My recent update of gaoptim package brings up a new function, GAPerm, which can be used to perform combinatorial optimization using the Genetic Algorithm approach. The example below solves a TSP instance with 10 points around a circumference, the...

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R / Finance 2013 Recap — and Presentation Slides

The fifth internation R/Finance conference was held last weekend. As one of the founding co-organizers, I may well be accussed of a little bias, but we think we once again pulled off a very nice and successful weekend-long event. Participants had ki...

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Creating a presence-absence raster from point data

May 27, 2013
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Creating a presence-absence raster from point data

I’m working on generating species distribution models at the moment for a few hundred species. Which means that I’m trying to automate as many steps as possible in R to avoid having to click buttons hundreds of times in ArcView. … Continue reading →

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BISON USGS species occurrence data

May 27, 2013
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BISON USGS species occurrence data

The USGS recently released a way to search for and get species occurrence records for the USA. The service is called BISON (Biodiversity Information Serving Our Nation). The service has a web interface for human interaction in a browser, and two APIs (application programming interface) to allow machines to interact with their database. One of the...

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BISON USGS species occurrence data

May 27, 2013
By
BISON USGS species occurrence data

The USGS recently released a way to search for and get species occurrence records for the USA. The service is called BISON (Biodiversity Information Serving Our Nation). The service has a web interface for human interaction in a browser, and two APIs (application programming interface) to allow machines to interact with their database. One of the...

Read more »