R: Isarithmic Maps of Election Data (1/2)

September 12, 2012
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R: Isarithmic Maps of Election Data (1/2)

In this tutorial I will show

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Testing highlight.js with R code

I searched for a javascript plugin to highlighter code, but obviously not any code. I needed to higlight R. Finally I founded highlight.js. Highlights.js is pretty cool for many reasons. I like Highlights.js because: Support R lenguage. It's easy to use. Works automatically. That's mean you don't have to put the code what are you writing. Highloght it does alone. A lot of...

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Testing highlight.js with R code

I searched for a javascript plugin to highlighter code, but obviously not any code. I needed to higlight R. Finally I founded highlight.js. Highlights.js is pretty cool for many reasons. I like Highlights.js because: Support R lenguage. It's easy to use. Works automatically. That's mean you don't have to put the code what are you writing. Highloght it does alone. A lot of...

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Computational Finance with R on Coursera

September 12, 2012
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If you haven't signed up for the Introduction to Computational Finance and Financial Econometrics course taught by Eric Zivot on Coursera, it's not too late.  The second week just started and the first assignments aren't due until September 18th.J...

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Tutorials for Learning Visualization in R

September 12, 2012
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Tutorials for Learning Visualization in R

Today's guest post comes from Nathan Yau. Nathan runs FlowingData, a site on statistics and visualization, and is the author of Visualize This. Years ago, when I started FlowingData, the purpose of the blog was to catalog and think out loud about visualization, in its many varieties. In the beginning I was talking to myself for the most part,...

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Association and concordance measures

September 12, 2012
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Association and concordance measures

Following the course, in order to define assocation measures (from Kruskal (1958)) or concordance measures (from Scarsini (1984)), define a concordance function as follows: let be a random pair with copula , and with copula . Then define the so-...

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Great Circles, Black Holes, and Community Events Part 2 of 3

September 12, 2012
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Great Circles, Black Holes, and Community Events Part 2 of 3

This post will examine the Heber Valley Railroad, a small town tourist attraction using event gravitational pull. Using the information from part 1 the two factors associated with the events gravity, the number of participants, and the distance they traveled. The number of participants can be shown using bar charts, histograms, and summary tables. The distance traveled...

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Let’s go! (and Disclaimer)

September 12, 2012
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Let's get that started ...Fun stuff with R coming soon!Disclaimer beforehand:The analyses I'll present are not meant to be taken too seriously in a scientific way. I just wanna show what you can do with R as a programming language, basic statistics and...

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Review of “Numerical Methods and Optimization in Finance” by Gilli, Maringer and Schumann

September 12, 2012
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Review of “Numerical Methods and Optimization in Finance” by Gilli, Maringer and Schumann

Previously This book and the associated R package were introduced before. Executive Summary A very nice — and enlightening — discussion of a wide range of topics. Principles The Introduction to the book sets out 5 principles.  This is probably the most important part of the book.  The principles are: We don’t know much in … Continue reading...

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How to check your package with R-devel

September 12, 2012
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In response to an update to ggplot2 (now verson 0.9.2) I had to make some minor changes to our package TripleR. The CRAN maintainers also asked to … Please also fix other issues that may be apparent in checks with a current R-devel. Now, how can this be done? Here’s my workflow on Mac OS

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One-Way ANOVA

September 11, 2012
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One-Way ANOVA Analysis of variance is a tool used for a variety of purposes. Applications range from a common one-way ANOVA, to experimental blocking, to more complex nested designs. This first ANOVA example provides the necessary tools to analyze data using this technique. This example will show a basic one-way ANOVA. I will save the

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wordcloud makes words less cloudy

September 11, 2012
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wordcloud makes words less cloudy

  An update to the wordcloud package (2.2) has been released to CRAN. It includes a number of improvements to the basic wordcloud. Notably that you may now pass it text and Corpus objects directly. as in: #install.packages(c("wordcloud","tm"),repos="http://cran.r-project.org") library(wordcloud) library(tm) wordcloud("May our children and our children's children to a thousand generations, continue to enjoy the

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Fund Now or Buy Later? A Kickstarter Price Comparison

September 11, 2012
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Fund Now or Buy Later? A Kickstarter Price Comparison

Hi Internet! I’m Preeya, and I will be your guide in this blog’s quantitative quest for knowledge. To get started, let’s talk about pricing. Part of the Kickstarter process is figuring out how much a hypothetical product will cost once it’s on the market. But how accurately can that be calculated without actually going through … Continue reading...

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Integrate data and reporting on the Web with knitr

September 11, 2012
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Today's guest post comes from Yihui Xie, author of the knitr package — ed. Hi, this is Yihui Xie, and I'm guest posting on the Revolutions blog to talk about one aspect of the knitr package: how we can integrate data analysis and reporting in R with the Web. This post includes both the work that has been done...

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Big data analysis, for free, in R (or “How I learned to load, manipulate, and save data using the ff package”)

September 11, 2012
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Big data analysis, for free, in R (or “How I learned to load, manipulate, and save data using the ff package”)

Before choosing to support the purchase of Statistica at my workplace, I came across the ff package as an option for working with really big datasets (with special attention paid to ff dataframes, or ffdf). It looked like a good … Continue reading →

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Second Milano R net meeting

September 11, 2012
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Second Milano R net meeting

September 27, 2012 - 18:00 - 21:00 Fiori Oscuri Bistrot & Bar (www.fiorioscuri.it) Via Fiori Oscuri, 3 - Milano (Zona Brera) Continue reading →

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Connecting data to the real world – The next sexy job?

September 11, 2012
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Connecting data to the real world – The next sexy job?

At last week's Royal Statistical Society (RSS) conference Hal Varian, Chief Economist at Google, gave a panel talk about 'Statistics at Google'. Could he get a better audience than the RSS? Hal talked about his career in academia and at Google. He remi...

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Unit root, or not ? is it a big deal ?

September 10, 2012
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Unit root, or not ? is it a big deal ?

Consider a time series, generated using set.seed(1) E=rnorm(240) X=rep(NA,240) rho=0.8 X=0 for(t in 2:240){X=rho*X+E} The idea is to assume that an autoregressive model can be considered, but we don't know the value of the parameter. ...

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Extending Gold time series

September 10, 2012
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Extending Gold time series

While back-testing trading strategies I want all assets to have long history. Unfortunately, sometimes there is no tradeable stock or ETF with sufficient history. For example, I might use GLD as a proxy for Gold allocation, but GLD is only began trading in November of 2004. We can extend the GLD’s historical returns with its

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PDF and CDF for normal distributions with R

September 10, 2012
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PDF and CDF for normal distributions with R

Below, we give the R code to plot the PDF and the CDF for normal distributions. We wish to get charts quite similar to the ones read on Wikipedia (Normal Distribution). The resulting charts are shown at the bottom. Notice that … Continue reading →

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igraph 0.6 issues: Changed numbering of Vertices

September 10, 2012
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I have tried one of my previous scripts with an updated igraph version and I got an interesting (pretty much unexpected) error:At type_indexededgelist.c:269 : invalid (odd) length of edges vector, Invalid edge vectorThe problem is that it was a well-te...

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R-bloggers submission

September 10, 2012
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I might be the 393rd blogger on the R-bloggers.com :-)  http://www.r-bloggers.com/Wohoo!

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Item Response Theory: Developing Your Intuition

September 10, 2012
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Item Response Theory: Developing Your Intuition

Suppose that you accepted my argument from the last two posts on halo effects and bifactor models.  As you might recall, I argued that when respondents complete rating scales, they predominating rely on their generalized impression with a more minor role played by the specific features that the ratings were written to measure.  Consequently, we...

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Example 10.1: Read a file byte by byte

September 10, 2012
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Example 10.1: Read a file byte by byte

More and more makers of electronic devices use standard storage media to record data. Sometimes this is central to the device's function, as in a camera, so that the data must be easy to recover. Other times, it's effectively incidental, and the device maker may not provide easy access to the stored data....

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Population health management with RevoScaleR

September 10, 2012
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This guest post is by Douglas McNair MD PhD, Engineering Fellow & President, Cerner Math Inc. -- ed. RevoScaleR scaling big-data modeling performance for real-time health data analysis at Cerner The size of data sets is increasing much more rapidly than the speed of cores, of RAM, and of disk drives. This is particularly true of electronic health records...

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INLA functions (continued)

September 10, 2012
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INLA functions (continued)

I have polished up one of the two functions I've thought of implementing for INLA and it's now available in the development version of the R package. So if you've got INLA installed in your R version (see how you can do it here, if you don't), you...

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Progress bars in R using winProgressBar

September 10, 2012
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Progress bars in R using winProgressBar

Using progress bars in R scripts can provide valuable timing feedback during development and additional polish to final products. winProgressBar and setWinProgressBar are the primary functions for creating progress bars in R. Progress bars, and progress indicators in general, are relatively uncommon in R programming. This makes sense, as they can add bloat and, being design elements, they generally...

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Progress bars in R using winProgressBar

September 10, 2012
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Progress bars in R using winProgressBar

Using progress bars in R scripts can provide valuable timing feedback during development and additional polish to final products. winProgressBar and setWinProgressBar are the primary functions for creating progress bars in R. Progress bars, and progress indicators in general, are relatively uncommon in R programming. This makes sense, as they can add bloat and, being The post Progress...

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Great Circles, Black Holes, and Community Events Part 1 of 3

September 10, 2012
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About 8 years ago, I was sitting in class listening to a guest lecturer talk about how community events can be described like celestial bodies with their own gravity, where the size and importance of the event would attract more people, from farther away. Much like a black hole, where the bigger the mass of the black hole the...

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