Publications by Tal Galili
A speed test comparison of plyr, data.table, and dplyr
Guest post by Jake Russ For a recent project I needed to make a simple sum calculation on a rather large data frame (0.8 GB, 4+ million rows, and ~80,000 groups). As an avid user of Hadley Wickham’s packages, my first thought was to use plyr. However, the job took plyr roughly 13 hours to complete. plyr is extremely efficient and user frie...
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R 3.0.2 and RStudio 0.9.8 are released!
R 3.0.2 (codename “Frisbee Sailing”) was released yesterday. The full list of new features and bug fixes is provided below. Also, RStudio v0.98 (in a “secret” preview) was announced two days ago with MANY new features, including: Amazing new debugging tools(!) An engine for creating R presentations. You can see a detailed example for u...
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What’s the Most “Concave” State in the U.S.? Using R to Solve a Geography Puzzle
This is a guest post by Todd Schneider and the original link is http://news.rapgenius.com/Atodd-whats-the-most-concave-state-in-the-us-using-r-to-solve-a-geography-puzzle-lyrics. The puzzle: find two points inside the United States such that Both points are in the same state The straight line segment (shortest great circle) connecting them cross...
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New JerseyR User Group Meeting – 22nd October 2013, Iselin NJ
We are pleased to announce details of the next New Jersey R meeting; this is a free event open to anyone using or interested in using R. Venue: Hilton Woodbridge, 120 Wood Avenue South, Iselin, NJ 08830 Time: 6.30 pm – 10pm Presentations (from 7pm) • Using knitr to create reports – Adam Rich, Beazley Group �...
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Dealing with a stochastic fitness function in GA package
Guest post by Kim Man Lui, PhD. (about GA – an R package for optimization using genetic algorithms) The GA package (version 2.0) is a generic package in which one can define his/her own functions of fitness, selection, crossover and mutation. Among those functions, the most important is the fitness. However, in the GA package, the ...
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R User Group meetings in New Jersey, Basel, Manchester and London
Mango Solutions are pleased to announce the forthcoming free user group meetings for R users and enthusiasts. All meetings are free to attend and consist of a few R related presentations followed by networking time. If you are an R user or have an interest in R please come along. 22 October 2013 – New Jersey R – (www.newjerseyr.org ) 30...
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NYC R Programming Classes – starting this coming Sunday
Guest post by Vivian Zhang, original post. You can sign up for our Sunday Intensive beginner level R classes at NYC Data Science Academy meetup page or email [email protected] for more info. Brief: The course (which will meet five Sundays) will start from the basics, introducing the building blocks used for programming in R and building...
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R jobs (September, October 2013)
R-bloggers is offering an “R jobs” post, that will be published once every month (or other month). If you are interested in offering a job to be posted on r-bloggers, please e-mail me at: [email protected] (please write in the subject line the text “R job” so I could have easy e-mail filtering on it 🙂 ). statistics. co...
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ManchesterR and LondonR user group meetings
ManchesterR and LondonR user group meetings Mango Solutions advise details of the forthcoming R user group meetings in Manchester and London. These free meetings are open to anyone using R or interested in using R. ManchesterR Date: Wednesday 13th November Venue: The Cor...
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R-bloggers: an example of how interest networks propel viral events
A guest post by Jeff Hemsley, who has co-authored with Karine Nahon a new book titled Going Viral. ————————- In Going Viral (Polity Press, 2013) we explore the topic of virality, the process of sharing messages that results in a fast, broad spread of information. What does that have to do R, or the R-bloggers community? First an...
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