Monthly Archives: May 2010

Manual variable selection using the dropterm function

May 12, 2010
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Manual variable selection using the dropterm function

When fitting a multiple linear regression model to data a natural question is whether a model can be simplified by excluding variables from the model. There are automatic procedures for undertaking these tests but some people prefer to follow a more manual approach to variable selection rather than pressing a button and taking what comes

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Revolution Analytics and R in the news

May 12, 2010
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It was quite the media frenzy for Revolution and R last week. In conjunction with our relaunch as Revolution Analytics, we spoke to more than a dozen journalists and analysts to explain why we think R is at the center of a perfect storm for predictive analytics: with routine collection of large data sets, data analysis is now a...

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Reflections on consulting part 5 – what languages and tools to learn?

May 12, 2010
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Reflections on consulting part 5 – what languages and tools to learn?

What languages and tools should you learn as a math/stat consultant?  To jump to the answer: Excel/VBA, SQL, R, Java, and Python. Spreadsheets have many problems with verifiability and scalability, so why Excel? Excel is: Useful for prototyping ideas quickly, either for your own use or to show to other team members Well-known and understood

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What Social Network Analysis software do you use?

May 12, 2010
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What Social Network Analysis software do you use?

See a the poll here by Gabriel Rossman at Code and Culture. I voted for R and ‘igraph’. If you use R you are getting access to all the other wonderful things that come with R. Using specialized package, like Pajek, UCINET etc requires constant going back and forth between network software and some other

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Rcpp 0.8.0

May 12, 2010
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SummaryVersion 0.8.0 of the Rcpp package was released to CRAN today. This release marks another milestone in the ongoing redesign of the package, and underlying C++ library.OverviewRcpp is an R package and C++ library that facilitates integr...

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Collect and Parse GPS (NMEA0183) Data in R

May 11, 2010
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I recently wrote a serial connection for R-2.11.0 so that I can communicate with serial devices, for example an old Garmin eTrex Legend. This GPS device is able to output NMEA0183 sentences to a standard serial port (4800,8,1,N). I hooked up the device and used the serial connection to collect some data using some R

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Sweave for Reproducible Research and Beatiful Statistical Reports

May 11, 2010
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Frank Harrell, chair of the Biostatistics department here at Vanderbilt, is giving a seminar entitled "Sweave for Reproducible Research and Beautiful Statistical Reports" tomorrow, Wednesday, May 12, 1:30-2:30pm, in the MRBIII Conference Room 1220. This tutorial covers the basics of Sweave and shows how to enhance the default output in various ways by using: latex methods for converting R...

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Number Formatting

May 11, 2010
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Number Formatting

I was discussing some subject with my kids - can't recall if it was in the realm of astronomy, computing, or moder economics. In any case, it involved large numbers. I fired up R to do a quick calculation:> 1000000000 / 1000The resulting answer was ...

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R Package ‘rms’ for Regression Modeling

May 11, 2010
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If you attended Frank Harrell's Regression Modeling Strategies course a few weeks ago, you got a chance to see the rms package for R in action. Frank's rms package does regression modeling, testing, estimation, validation, graphics, prediction, and ty...

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Webinar May 20: Introduction to Revolution R

May 11, 2010
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I'll be giving a live webinar on Thursday next week (May 20) titled Introduction to Revolution R. If you're new to the R world and wondering what you can do with R, this webinar is for you. I'll also be introducing some of the functionality unique to Revolution R included in our Revolution R Community (free to everyone) and...

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