144 search results for "iris"

googleVis 0.2.17 is released: Displaying earth quake data

August 13, 2012
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googleVis 0.2.17 is released: Displaying earth quake data

The next version of the googleVis package has been released on the project site and CRAN. This version provides updates to the package vignette and a new example for the gvisMerge function. The new sections of the vignette have been featured on this ...

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Cheat sheet for prediction and classification models in R

August 9, 2012
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Cheat sheet for prediction and classification models in R

Ricky Ho has created a reference a 6-page PDF reference card on Big Data Machine Learning, with examples implemented in the R language. (A free registration to DZone Refcardz is required to download the PDF.) The examples cover: Predictive modeling overview (how to set up test and training sets in R) Linear regression (using lm) Logistic regression (using glm)...

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Spacing of multi-panel figures in R

August 2, 2012
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Spacing of multi-panel figures in R

In a previous post, I showed how to keep text and symbols at the same size across figures that have different numbers of panels. The figures in that post were ugly because they used the default panel spacing associated with the mfrow argument of the par( ) function. Below I will walk through how to

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Making R graphics legible in presentation slides

July 30, 2012
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Making R graphics legible in presentation slides

I only visited a few JSM sessions today, as I’ve been focused on preparing for my own talk tomorrow morning. However, I went to several talks in a row which all had a common problem that made me cringe: graphics … Continue reading →

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Error metrics for multi-class problems in R: beyond Accuracy and Kappa

July 6, 2012
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Error metrics for multi-class problems in R: beyond Accuracy and Kappa

The caret package for R provides a variety of error metrics for regression models and 2-class classification models, but only calculates Accuracy and Kappa for multi-class models.  Therefore, I wrote the following function to allow caret:::train t...

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Simple distribution plot in R

July 2, 2012
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Simple distribution plot in R

Plot the distribution of a sample as bars and add a histogram line for visualizing the sample characteristics.No related posts.

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Figuring an exchange rate for sports scores

June 26, 2012
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While the US's Major League Soccer is using advanced analytics to analyze ball movement and improve team composition, they might want to think about a smaller, but possibly more impactful, goal for analytics. Like, how to explain to an American audience what a 1-2 game means to a basketball or baseball fan not familiar with scoring in the beautiful...

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How to Convert Rugby into Football/Soccer Scores

June 26, 2012
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How to Convert Rugby into Football/Soccer Scores

Following the Irish rugby team’s humiliating 60-0 defeat to New Zealand, an interesting question was posed on Twitter: what does a 60-0 result convert to in football/soccer? Intrigued, I decided to gather some data from both the English premier league (this season, more data collected and future blog posts to come!) and the equivalent English

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Time-Series Policy Evaluation in R

May 21, 2012
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Time-Series Policy Evaluation in R

Quantifying the success of government policies is clearly important. Randomized control trials, like those conducted by drug companies, are often described as the ‘gold-standard’ for policy evaluation. Under these, a policy is implemented in/to one area/group (treatment), but not in/to another (control). The difference in outcomes between the two areas or groups represents the effectiveness

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Emulating local static variables in R

May 17, 2012
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Emulating local static variables in R

Recently I was writing a code allowing to plot multiple ggplot2 plots on one page. I wanted to replicate standard behavior of  plot  function that plots graphs in sequence according to  mfrow/ mfcol option in par...

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