956 search results for "how to import image file to R"

John Snow’s Cholera data in more formats

March 13, 2013
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John Snow’s Cholera data in more formats

In honour of the bicentenary of John Snow’s birth – and because I was asked to by someone via email – I have now released my digitisation of John Snow’s Cholera data in a few other formats: KML and as Google Fusion Tables. To save you reading my previous blog posts on the subject, I’ll

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Using maps and ggplot2 to visualize college hockey championships

March 13, 2013
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Using maps and ggplot2 to visualize college hockey championships

Short: I plot the frequency of college hockey championships by state using the maps package, and ggplot2 Note: this example is based heavily on the example provided athttp://www.dataincolour.com/2011/07/maps-with-ggplot2/ data reference:http://en.wikipedia.org/wiki/NCAA_Men%27s_Ice_Hockey_Championship Question of interestAs a good Minnesotan, I've believed for quite some time that the colder, Northern states enjoy a competitive advantage when it...

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Lipsyncing for your life: a survival analysis of RuPaul’s Drag Race

March 11, 2013
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Lipsyncing for your life: a survival analysis of RuPaul’s Drag Race

If you follow me on Twitter, you know that I’m a big fan of RuPaul’s Drag Race. The transformation, the glamour, the sheer eleganza extravanga is something my life needs to interrupt the monotony of grad school. I was able to catch up on nearly four seasons in a little less than a month, and I’ve been watching the… Continue reading →

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Discovering Argon with the 2-Sample t-Test

Discovering Argon with the 2-Sample t-Test

I learned about Lord Rayleigh’s discovery of argon in my 2nd-year analytical chemistry class while reading “Quantitative Chemical Analysis” by Daniel Harris.  (William Ramsay was also responsible for this discovery.)  This is one of my favourite stories in chemistry; it illustrates how diligence in measurement can lead to an elegant and surprising discovery.  I find

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Getting flexible with SAP HANA

Getting flexible with SAP HANA

Most of you might not be aware of a feature introduced on SAP HANA SPS5. This new feature is called "Flexible Tables", which means that you can define a table that will grow depending on your needs. Let's see an example...You define a table with ID, NA...

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Visualizing Risky Words — Part 2

March 9, 2013
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Visualizing Risky Words — Part 2

This is a follow-up to my Visualizing Risky Words post. You’ll need to read that for context if you’re just jumping in now. Full R code for the generated images (which are pretty large) is at the end. Aesthetics are the primary reason for using a word cloud, though one can pretty quickly recognize what

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Comparing quantiles for two samples

March 8, 2013
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Comparing quantiles for two samples

Recently, for a research paper, I some samples, and I wanted to compare them. Not to compare they means (by construction, all of them were centered) but there dispersion. And not they variance, but more their quantiles. Consider the following boxplot type function, where everything here is quantile related (which is not the case for standard boxplot, see http://freakonometrics.hypotheses.org/4138,...

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Easily plotting grouped bars with ggplot #rstats

March 5, 2013
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Easily plotting grouped bars with ggplot #rstats

Summary This tutorial shows how to create diagrams with grouped bar charts or dot plots with ggplot. The groups can also be displayed as facet grids. Importing the data from SPSS All following examples are based on an imported SPSS … Weiterlesen →

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Load Balanced Parallelization with snowfall

March 5, 2013
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Load Balanced Parallelization with snowfall

For some reason, I didn't notice a few months ago the best way to perform a parallelized version of Lapply with package snowfall. We implemented the parallel version of function lapply with the function sfLapply, in the development of our pipeline p...

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Visualizing neural networks from the nnet package

March 4, 2013
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Visualizing neural networks from the nnet package

Neural networks have received a lot of attention for their abilities to ‘learn’ relationships among variables. They represent an innovative technique for model fitting that doesn’t rely on conventional assumptions necessary for standard models and they can also quite effectively handle multivariate response data. A neural network model is very similar to a non-linear regression

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