167 search results for "pca"

Visualising Tourism Data using R with googleVis package

December 20, 2012
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Visualising Tourism Data using R with googleVis package

Inspired by Mages’s post on Accessing and plotting World bank data with R (using googleVis package), I created one visualising tourism receipts and international tourist  arrivals of various countries since 1995. The data used are from the World Bank’s country indicators. To see the motion chart, double click a picture below.  Code Filed under: R, Tourism

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Finding a pin in a haystack – PCA image filtering

December 4, 2012
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Finding a pin in a haystack – PCA image filtering



I found the following post regarding the anomalous metal object observed in a Curiosity Rover photo to be fascinating - specifically, the clever ways that some programmers used for filtering the image for the object. The following answer on mathematica.stackexchange.com was especially illuminating for its use of a multivariate distribution to...

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A thermometer in R using Arduino and Java

November 11, 2012
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A thermometer in R using Arduino and Java

A couple of weeks ago, Markus Gesmann demonstrated the feasability of connecting R and Arduino using Processing and Rserve in a nice and simple example. This actually rekindled my interest in Arduino that I hadn’t had time to satisfy… Agai...

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analyze the national survey on drug use and health (nsduh) with r

November 6, 2012
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the national survey on drug use and health (nsduh) monitors illicit drug, alcohol, and tobacco use with more detail than any other survey out there.  if you wanna know the average age at first chewing tobacco dip, the prevalence of needle-sharing,...

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Machine learning for hackers

October 23, 2012
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Machine learning for hackers

Which way do you prefer to learn a new material – deep theoretical background first and practice later or do you like to break things in order to fix them? If latter is your way of learning things, then most likely you will enjoy Machine Learning for Hackers. The book has chapters on machine learning

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Looking to the PCA scores with GGobi

October 21, 2012
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Looking to the PCA scores with GGobi

In this post I continue with the unsupervised exploration of oil spectra, which we have seen in previous post ( PCA with "ChemoSpec" - 001).In the manual "ChemoSpec:An R Package for Chemometric Analysis of Spectroscopic Data", (page 23) there is a brie...

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PCA with "ChemoSpec" – 001

October 20, 2012
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PCA with "ChemoSpec" – 001

In my last post about "ChemoSpec package" (Hierarchical Cluster Analysis (ChemoSpec) - 02), we saw the two cluster groups (one for olive oil, other for sunflower oil), and also another sub-clusters for the sunflower oil.Continue reading the manual "Che...

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Color Palettes in HCL Space

October 12, 2012
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Color Palettes in HCL Space

This is a quick follow-up to my previous post about Color Palettes in RGB Space. Achim Zeileis had commented that, perhaps, it would be more informative to evaluate the color palettes in HCL (polar LUV) space, as that spectrum more accurately describes how humans perceive color. Perhaps more clear trends would emerge in HCL space,

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Long-term precipitation data for your location from the US Historical Climatology Network using R

September 19, 2012
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Long-term precipitation data for your location from the US Historical Climatology Network using R

Abstract Long-term daily precipitation records from the US Historical Climatology Network (USHCN) are processed and summarized using R. Below is R code which examines the data from Livermore, CA, the closest available USHCN station to my present home ...

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DESeq vs edgeR Comparison

September 18, 2012
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DESeq vs edgeR Comparison

Update (Dec 18, 2012): Please see this related post I wrote about differential isoform expression analysis with Cuffdiff 2.DESeq and edgeR are two methods and R packages for analyzing quantitative readouts (in the form of counts) from high-throughput e...

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