Monthly Archives: May 2012

Review: “Forest Analytics with R: an introduction”

May 29, 2012
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Review: “Forest Analytics with R: an introduction”

Forestry is the province of variability. From a spatial point of view this variability ranges from within-tree variation (e.g. modeling wood properties) to billions of trees growing in millions of hectares (e.g. forest inventory). From a temporal point of view … Continue reading →

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Google Earth and ocean depth contours

May 29, 2012
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Google Earth and ocean depth contours

Been playing around in R for a while and then a bit in the GIS environment - within R of course. Do not know very much about GIS, but know what I want: Looking at GIS fisheries data across various scales (macro to global). Now we have myriads of websit...

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Better decision tree graphics for rpart via party and partykit

May 29, 2012
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I’ve been using Graphviz to create better decision tree graphics “by hand” for rpart objects created in R (final tree). I stumbled on this post that shows how one could convert an rpart object to a party project via the as.party function in partykit to utilize the plot functions in party. It looks quite nice.... Read more »

Exporting from Win ISI / Importing into R

May 29, 2012
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Exporting from Win ISI / Importing into R

Chemometric software´s  have the option to export a matrix to a TXT file (in this case a constituents matrix), in a way we can import it easily into R, to work with. It is the first step to go into the R world.I use in this case Win ISI Soft...

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Mahalanobis distance with "R" (Exercice)

May 29, 2012
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Mahalanobis distance with "R" (Exercice)

I have developed this exercise with Excel in another post for the same calculations , I am going to develop  it this time with  "R".    edad  long.  peso    mg.kg1    28 &n...

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Project Euler — problem 4

May 29, 2012
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Project Euler — problem 4

It’s midnight already. I’m going to bed after I type this. Now the fourth Euler problem: A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 99. Find … Continue reading →

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How to Stay Current in Bioinformatics/Genomics

May 29, 2012
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A few folks have asked me how I get my news and stay on top of what's going on in my field, so I thought I'd share my strategy. With so many sources of information begging for your attention, the difficulty is not necessarily finding what's interesting...

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Choosing colour palettes. Part I: Introduction

May 29, 2012
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Choosing colour palettes. Part I: Introduction

In this series of three posts, we’ll look at colours in R graphics produced with ggplot2: what are the available choices of colour schemes, and how to choose a colour palette most suitable for a particular graphic? In kindergarten, choosing a co...

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Example 9.33: Multiple imputation, rounding, and bias

May 29, 2012
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Example 9.33: Multiple imputation, rounding, and bias

Nick has a paper in the American Statistician warning about bias in multiple imputation arising from rounding data imputed under a normal assumption. One example where you might run afoul of this is if the data are truly dichotomous or count variables, but you model it as normal (either because your software is unable to model dichotomous...

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knitr, Slideshows, and Dropbox

May 29, 2012
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knitr, Slideshows, and Dropbox

I just noticed that Markus Gesmann has a nice post on using RStudio, knitr, Pandoc, and Slidy to create slideshows. After my recent attempt to use deck.rb to turn a Markdown/knitr file into a deck.js presentation I caved in and also decided to go with ...

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