How to search the documentation of all CRAN packages

April 5, 2011
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How to search the documentation of all CRAN packages

Ever tried to find a specific function or algorithm in R that you're sure that someone has implemented in a CRAN package, but you don't know which one? Now you can find it, in the R Packages section of R community site inside-R.org. The R Packages section now includes the ability to browse and search help files from R...

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Using rApache for Web Services

April 5, 2011
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Ran across a technical report I wrote in April 2009 regarding my work linking REDCap with rApache. Here’s the introductory text and a link to the original report (note that way back then I was calling it Rapache - now it’s rApache - don’t ask): ...

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Rcpp 0.9.3

April 5, 2011
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A brand new and shiny 0.9.3 release of Rcpp is now on CRAN and Debian. This version contains an actual bug fix for Rcpp modules and a few build improvements, including for both clang/llvm and g++-4.6 (which, being in Debian, is already used for c...

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Example 8.33: Merging data sets one-to-many

April 5, 2011
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Example 8.33: Merging data sets one-to-many

It's often necessary to combine data from two data sets for further analysis. Such merging can be one-to-one, many-to-one, and many-to-many. The most common form is the one-to-one match, which we cover in section 1.5.7. Today we look at a one-to-man...

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How to: Multinomial regression models in R

April 5, 2011
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How to: Multinomial regression models in R

Apples, oranges, pears or bananas? Bus, train, car, or walk? Many choices are made between more than two options, a situation that can be represented by multinomial choice modelling. Here's a quick tutorial on how to do it in R.

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Painting a picture of statistical packages

April 4, 2011
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Painting a picture of statistical packages

Imagine you have to analyze text comprising 18,000 words. You have to identify the most commonly cited ideas or words in the text and then present the analysis in a graphic format. There are sophisticated tools out there to help you with this task, but then again there is a tight deadline. You have fewer than five minutes to...

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Painting a picture of statistical packages

April 4, 2011
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Painting a picture of statistical packages

Imagine you have to analyze text comprising 18,000 words. You have to identify the most commonly cited ideas or words in the text and then present the analysis in a graphic format. There are sophisticated tools out there to help you with this task, but then again there is a tight deadline. You have fewer than five minutes to...

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R 101: Vectors

Vectors are a basic data structure in R and are created using the c() function. Unlike data frames and lists, the elements of a vector must be of the same mode. Functions can be used on a vector. For example, length(x) can be used to find the number of elements in x. Furthermore, conditions can

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Book: ggplot2 by Hadley Wickham

April 4, 2011
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Book: ggplot2 by Hadley Wickham

All my recent plots are built using ggplot2 package. I don’t know if my dear readers have noticed the difference, but from my point of view, ggplot2 allows to create nice looking and aesthetics plots. I was using this package before, but the real boost came after reading this book: ggplot2: Elegant Graphics for Data Analysis (Use R).

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Comparison of compression

April 4, 2011
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Comparison of compression

I recently wrote an email with an attached LZMA archive. It was immediately answered with something like: "What are you doing? I had to boot linux to open the file!" First of all I don't care whether user of proprietary systems are able to read open formats, but this answer made me curious to know about the differences between some compression...

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RQuantLib Windows binary on CRAN

April 4, 2011
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Dirk Eddelbuettel has recently released RQuantLib-0.3.7, which contains the necessary QuantLib builds to allow the CRAN servers to build the Windows binary.This (thankfully) makes my post on how to build RQuantLib on 32-bit Windows unnecessary for casu...

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RQuantLib Windows binary on CRAN

April 4, 2011
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Dirk Eddelbuettel has recently released RQuantLib-0.3.7, which contains the necessary QuantLib builds to allow the CRAN servers to build the Windows binary.This (thankfully) makes my post on how to build RQuantLib on 32-bit Windows unnecessary for casu...

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The structure of twitter participant relationships in conversations around #Libya, #Bieber, and #Rstats

April 4, 2011
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I am a recent comer to twitter, and it took me a few weeks to figure out what this was all about. Who are all these people tweeting each other and what do all these trending hashtags mean? Do these … Continue reading →

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Day #16-17 R-scripting templates in knime

To install the community nodes in knime: help > install new software > http://tech.knime.org/update/community-contributions/release you’ll only need the “R and Groovy scripting extensions for KNIME” What is it and what does it...

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Day #17 Creating your own R-scripting-template

First, go take a look at this website: http://rgg.r-forge.r-project.org/docs.html At “6. RGG Elements” you can see which GUI elements you can give to the user and which functions they have. Then, open a textfile and call it however you want...

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RQuantLib 0.3.7

April 4, 2011
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A build-fix release RQuantLib 0.3.7 is now on CRAN and in Debian. RQuantLib combines (some of) the quantitative analytics of QuantLib with the R statistical computing environment and language. Thanks to the help by Brian Ripley (who compiled Quan...

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RcppArmadillo 0.2.18

April 4, 2011
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Conrad Sanderson made a bug-fix release (1.1.92) by for his wonderful Armadillo templated C++ library for linear algebra appeared yesterday and as usual a new release 0.2.18 of RcppArmadillo, our Rcpp-based integration into R is now on CRAN mirrors. ...

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How to Shade Under a Normal Density in R

April 3, 2011
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How to Shade Under a Normal Density in R

The easiest-to-find method for shading under a normal density is to use the polygon() command. That link is to the first hit on Google for "Shading Under a Normal Curve in R." It works (like a charm), but it is not the most intuitive way to let users p...

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Feed Your (Machine) Brain

April 3, 2011
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Feed Your (Machine) Brain

Few can tell you what goes into a chicken nugget, but most will agree that it's good for your brain. If you're a little sluggish and can't focus, what do you normally do? That's right, you pop a couple chicken nuggets. And similar to our brains, our al...

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Interestingness Measures

Interestingness Measures

Probably because I first encountered them somewhat late in my professional life, I am fascinated by categorical data types.  Without question, my favorite book on the subject is Alan Agresti’s Categorical Data Analysis (Wiley Series in Probabili...

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Maps of solar radiation

Maps of solar radiation

The Atmospheric Science Data Center (ASDC) at NASA Langley Research Center offers several data sources. For example, it is possible to download a text file with the 22-year (July 1983 – June 2005) monthly and annual average of global horizontal irradiation. nasafile <- 'http://eosweb.larc.nasa.gov/sse/global/text/global_radiation' nasa <- read.table(file=nasafile, skip=13, header=TRUE) With this data, R and the

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Violin and boxplots with lattice and R

Violin and boxplots with lattice and R

A violin plot is a combination of a boxplot and a kernel density plot. Lattice includes the panel.violin function for this graphical tool. This example draws a violin and a boxplot together. First, let’s download some solar radiation data from the NASA webpage: nasafile <- 'http://eosweb.larc.nasa.gov/sse/global/text/global_radiation' nasa <- read.table(file=nasafile, skip=13, header=TRUE) Now, I plot a

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A very short and unoriginal introduction to snow

April 2, 2011
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As Jian-Feng rightly pointed out in a comment on my guide to setting up snow on the OSC cluster, it was probably somewhat cavalier of me to say: Getting snow to run properly on single machines, or ever with a cluster of … Continue reading →

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Find NHL Players with 30 Goals and 100 PIM using R

April 2, 2011
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Find NHL Players with 30 Goals and 100 PIM using R

Last week Jack Edwards raised the fact that Milan Lucic was the first Bruin player to join the 30 Goal / 100 Penalty Minute club in a few years.  It got me thinking about the other players who have accomplished … Continue reading →

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Plot the Scoring Streak of an NHL Player with R

April 1, 2011
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Plot the Scoring Streak of an NHL Player with R

I am a big Boston Bruins fan and have enjoyed the ups and downs over the last few years, regardless of the catastrophes that have occurred during the playoffs.  The team struggled a few weeks ago, but have recently seemed … Continue reading →

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Phylometa from R – UDPATE

April 1, 2011
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Phylometa from R – UDPATE

A while back I posted some messy code to run Phylometa from R, especially useful for processing the output data from Phylometa which is not easily done. The code is still quite messy, but it should work now. I have run the code with tens of different d...

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Bond Market as a Casino Game Part 1

April 1, 2011
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Bond Market as a Casino Game Part 1

With this post, I am doing something I try very hard to avoid, especially when communicating to my clients, and that is blurring the line between investing and gambling.  But after reading all of Reuven Brenner’s books and finishing Ralph Vince ...

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Program announced for R/Finance 2011

April 1, 2011
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R/Finance, the conference devoted to users of R in the financial sector, takes place every year in Chicago. The program has just been announced for R/Finance 2011 (to be held April 29 and 30), and it's jam-packed with talks from on automated trading, financial risk, hedge ratios, stochastic volatility, and much, much, more. Here's the announcement from the organizers:...

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R ready to Deduce you

April 1, 2011
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R ready to Deduce you

Despite being one of the most powerful computing platforms, and being free at the same time, R still struggles against other statistical software, such as SPSS and SAS, in gaining mass appeal amongst users of statistical and market intelligence software. Many have cited the absence of a user-friendly graphical user interface (GUI)...

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