Google Summer of Code advances R

September 28, 2010
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For the third year running, the Google Summer of Code program has sponsored a number of students working with R, and has again resulted in several new contributions expanding R in various fields. Dirk Eddelbuettel, who coordinated the R-related projects for GSoC in 2010, summarized the results, with details about the new packages now available for R thanks to...

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Example 8.7: Hosmer and Lemeshow goodness-of-fit

September 28, 2010
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Example 8.7: Hosmer and Lemeshow goodness-of-fit

The Hosmer and Lemeshow goodness of fit (GOF) test is a way to assess whether there is evidence for lack of fit in a logistic regression model. Simply put, the test compares the expected and observed number of events in bins defined by the predicted p...

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A Slider to Control Two Plotting Windows

September 28, 2010
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One of my readers asked two weeks ago how to control two graphics windows with the slider in gWidgets. Here is a simple example: if (!require("gWidgetsRGtk2")) install.packages("gWidgetsRGtk2") library(gWidgetsRGtk2) options(guiToolkit = "RGtk2") graphics.off() x11() x11() dev.set() gslider(from = 1, to = 100, value = 10,     container = gwindow("Two Plotting Windows"), handler = function(h, ...) {

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What is wrong with this graph?

September 28, 2010
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What is wrong with this graph?

This is a graph from our surveys with the University of Munich in B&H about ten years ago.(Click on it to see a large version.) In previous presentations (but not in peer-reviewed journals) I have talked about the peak on the subscale of Paranoid Ideation for the B&H samples. But looking at it again I

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What is wrong with this graph?

September 28, 2010
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What is wrong with this graph?

This is a graph from our surveys with the University of Munich in B&H about ten years ago.(Click on it to see a large version.) In previous presentations (but not in peer-reviewed journals) I have talked about the peak on the subscale ...

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Some hints for the R Beginner: Avoiding "blank screen syndrome"

September 27, 2010
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For new users, starting R for the first time can be a little daunting. Luckily, Patrick Burns of Burns Statistics has put together a handy tutorial to help the first-time R user get beyond "blank screen syndrome": So you have successfully started R on your machine. Here's where the trouble sometimes starts -- there's a big, huge prompt daring...

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Galton & simulation

September 27, 2010
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Galton & simulation

Stephen Stigler has written a paper in the Journal of the Royal Statistical Society Series A on Francis Galton’s analysis of (his cousin) Charles Darwin’ Origin of Species, leading to nothing less than Bayesian analysis and accept-reject algorithms! “On September 10th, 1885, Francis Galton ushered in a new era of Statistical Enlightenment with an address

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Mean reverting strategies and volatility

September 27, 2010
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Mean reverting strategies and volatility

Mean reverting strategies are beating on mean reversion of the prices. There are various flavors of mean reverting strategies, but as a proxy I chose RSI(2). You can find many entries on blogosphere about this strategy, but nowadays its popularity dried up. What made me wondering is that there was an idea about correlation between return

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How to send an HTTP PUT request from R

September 27, 2010
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How to send an HTTP PUT request from R

I wanted to get R talking to CouchDB. CouchDB is a NoSQL database that stores JSON documents and exposes a ReSTful API over HTTP. So, I needed to issue the basic HTTP requests: GET, POST, PUT, and DELETE from within R. Specifically, to get started, I wanted to add documents to the...

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How to send an HTTP PUT request from R

September 27, 2010
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How to send an HTTP PUT request from R

I wanted to get R talking to CouchDB. CouchDB is a NoSQL database that stores JSON documents and exposes a ReSTful API over HTTP. So, I needed to issue the basic HTTP requests: GET, POST, PUT, and DELETE from within R. Specifically, to get started, I...

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Riemann, Langevin & Hamilton [reply]

September 27, 2010
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Riemann, Langevin & Hamilton [reply]

Here is a (prompt!) reply from Mark Girolami corresponding to the earlier post: In preparation for the Read Paper session next month at the RSS, our research group at CREST has collectively read the Girolami and Calderhead paper on Riemann manifold Langevin and Hamiltonian Monte Carlo methods and I hope we will again produce a

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Mumbai 2010: R Course for Finance

September 27, 2010
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(This article was first published on Rmetrics blogs, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and comment on his blog: Rmetrics blogs. R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web...

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Maps with ggplot2

September 27, 2010
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Maps with ggplot2

The ggplot2 package offers powerful tools to plot data in R. The plots are designed to comply with the “grammar of graphics” philosophy and can be produced to a publishable level relatively easily. For users wishing to create a good map without too much thought I would recommend this worksheet. For those without their own

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RcppArmadillo 0.2.7

September 26, 2010
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Version 0.2.7 of RcppArmadillo is now on CRAN. This updates the included Armadillo template library to version 0.9.80 which Conrad released a few days ago. RcppArmadillo makes it easy to write highly efficient and highly readable C++ code for linear al...

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RcppArmadillo 0.2.7

September 26, 2010
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Version 0.2.7 of RcppArmadillo is now on CRAN. This updates the included Armadillo template library to version 0.9.80 which Conrad released a few days ago. RcppArmadillo makes it easy to write highly efficient and highly readable C++ code for linear...

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Animation

September 25, 2010
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Animation

A couple hours work and we now have animations of the global anomalies: Created with the animation package in R.  The code examples were a bit terse about some of the details but after fiddling about I was able to get  the program to output an Html animation complete with java based playback controls. Write

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GotoBLAS2

September 25, 2010
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Here are some tips to speedup matrix computation in R. The author did not provide any benchmark though.

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GotoBLAS2

September 25, 2010
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Here are some tips to speedup matrix computation in R. The author did not provide any benchmark though.

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Visualising questionnaires

September 25, 2010
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Visualising questionnaires

Last week I was shown the results of a workplace happiness questionnaire. The plots were ripe for a makeover. Most obviously, the pointless 3D effect needs removing, and the colour scheme is badly chosen.

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Two New R Packages: log4r and SortableHTMLTables

September 25, 2010
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I’ve just released two new packages for R: log4r and SortableHTMLTables. log4r is a minimal logging utility for R that’s inspired by the log4j family of logging tools. It has substantially fewer features than other logging tools for R, but it’s hopefully easier to use. SortableHTMLTables uses brew and the jQuery Tablesorter plugin to provide

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Damn Close 5.0

September 24, 2010
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Damn Close 5.0

Code will be in the drop box in a bit, once I shower:   This is a wholesale replacement of previous versions, completely rewritten in raster. It will be the base going forward. All of the analysis routines will be rewritten using raster.  For time series functionality I will continue to use zoo as that

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Find Duplicate Records in a File

September 24, 2010
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Find Duplicate Records in a File

In the world of data preparation a common task is to identify duplicate records in a file or data set.  A few years ago, I did most development work in Java, and shudder to think of the amount of code required to accomplish this sort of task. &nbs...

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Find Duplicate Records in a File

September 24, 2010
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Find Duplicate Records in a File

In the world of data preparation a common task is to identify duplicate records in a file or data set.  A few years ago, I did most development work in Java, and shudder to think of the amount of code required to accomplish this sort of task. &nbs...

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Because it’s Friday: Statistician vs Scientist

September 24, 2010
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This video brings flashbacks for my days as a statistics consultant to a medical school. Some days we just weren't speaking the same language... (With thanks to reader MK for the tip: "It's funny because it is true...".)

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Making sense of MapReduce

September 24, 2010
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From guest blogger Joseph Rickert. Last night I went to hear Ken Krugler of Bixolabs talk about Hadoop at the monthly meeting of the Software Developers Forum. Maybe because Ken is an unusually lucid speaker, or maybe because I just reached some sort of cumulative tipping point through the prep work of all those patient people who have tried...

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Connecting to a MongoDB database from R using the C API for MongoDB

September 24, 2010
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Today, Neil posted an article titled" Connecting to a MongoDB database from R using Java". In the current post, I'll show how to use the C API for MongoDB to fetch some MongoDB data from R. The code will be somehow similar to my previous post "A stateful C function for R: parsing Fasta sequences".OK, First, let's...

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Connecting to a MongoDB database from R using the C API for MongoDB

September 24, 2010
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Today, Neil posted an article titled" Connecting to a MongoDB database from R using Java". In the current post, I'll show how to use the C API for MongoDB to fetch some MongoDB data from R. The code will be somehow similar to my previous post "A stateful C function for R: parsing Fasta sequences".OK, First, let's...

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R / Finance 2011 Call for Papers

September 24, 2010
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Brian announced it on r-help and r-sig-finance and I have since updated the R/Finance website and Call for Papers page. And as David Smith already outblogged me about it, without further ado our Call for Paper for next spring's R/Finance conference: ...

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R / Finance 2011 Call for Papers

September 24, 2010
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Brian announced it on r-help and r-sig-finance and I have since updated the R/Finance website and Call for Papers page. And as David Smith already outblogged me about it, without further ado our Call for Paper for next spring's R/Finance conference: ...

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