1233 search results for "tutorial"

unsupervised classification of a Landsat image in R: the whole story or part two

August 1, 2012
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unsupervised classification of a Landsat image in R: the whole story or part two

The main question when using remote sensed raster data, as we do, is the question of NaN-treatment. Many R functions are able to use an option like rm.NaN=TRUE to treat these missing values. In our case the kmeans function in R is not capable to use such a parameter. After reading the tif-files and creating

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More on Horizon Charts

August 1, 2012
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More on Horizon Charts

for background please see prior posts Application of Horizon Plots, Horizon Plot Already Available, and Cubism Horizon Charts in R Some feedback has led me to think that I might have been a little ambitious with my last post on horizon charts. I though...

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Genetic algorithms: a simple R example

August 1, 2012
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Genetic algorithms: a simple R example

Genetic algorithm is a search heuristic. GAs can generate a vast number of possible model solutions and use these to evolve towards an approximation of the best solution of the model. Hereby it mimics evolution in nature. GA generates a population, the individuals in this population (often called chromosomes) have  Read more »

Genetic algorithms: a simple R example

August 1, 2012
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Genetic algorithms: a simple R example

Genetic algorithm is a search heuristic. GAs can generate a vast number of possible model solutions and use these to evolve towards an approximation of the best solution of the model. Hereby it mimics evolution in nature. GA generates a population, the individuals in this population (often called chromosomes) have a given state. Once the population is generated, the state of these individuals is evaluated...

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Bio7 1.6 for Windows and Linux released!

August 1, 2012
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Bio7 1.6 for Windows and Linux released!

01.08.2012 Finally i released a new version of Bio7 with many improvements and new features. Updated tutorials are available, too. The new Bio7 1.6 release can be downloaded here. Please also download the examples *.zip file from the sourceforge website which contains new examples for Bio7 1.6 (e.g. an example to cluster an image folder with

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Learning R has really made me appreciate SAS

July 25, 2012
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For the past 18 months, it seems like all I’ve heard about in the digital marketing industry is “big data”, and with that, mentions of using Hadoop and R to solve these sorts of problems.  Why are these tools the … Continue reading →Learning R has really made me appreciate SAS is an article from randyzwitch.com,...

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Faster R in Hadoop: rmr 1.3 now available

July 23, 2012
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The RHadoop project continues the Big Data integration of R and Hadoop, with a new update to its rmr package. Version 1.3 of rmr improves the performance of map-reduce jobs for Hadoop written in R. New features include: An optional vectorized API for efficient R programming when dealing with small records. Fast C implementations for serialization and deserialization from...

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Bayesian Inference Using OpenBUGS

July 22, 2012
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Bayesian Inference Using OpenBUGS

In our previous statistics tutorials, we have treated population parameters as fixed values, and provided point estimates and confidence intervals for them. An alternative approach is the Bayesian statistics. It treats population parameters as random...

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Processing Public Data with R

July 13, 2012
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Processing Public Data with R

I use R aplenty in analysis and thought it might be worthwhile for some to see the typical process a relative newcomer goes through in extracting and analyzing public datasets In this instance I happen to be looking at Canadian air pollution statistics. The data I am interested in is available on the Ontario Ministry

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Analysing time course microarray data using Bioconductor: a case study using yeast2 Affymetrix arrays

July 13, 2012
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Analysing time course microarray data using Bioconductor: a case study using yeast2 Affymetrix arrays

A few years ago I was involved in analysing some time-course microarray data. Our biological collaborators were interested in how we analysed their data, so this lead to a creation of tutorial, which in turn lead to a paper. When we submitted the paper, one the referees “suggested” that we write the paper using Sweave;

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