Monthly Archives: May 2013

Passing columns of a dataframe to a function without quotes

May 6, 2013
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Passing columns of a dataframe to a function without quotes

I love the syntax of calls to lm and ggplot, wherein the dataframe is specified as a variable and specific columns are referenced as though they were separate variables. While developing some of my functions, I’d wanted to introduce something similar. I often find that I have a single large dataframe and want to execute

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xkcd: Visualized

May 6, 2013
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xkcd: Visualized

IntroductionIt's been said that the ideal job is one you love enough to do for free but are good enough at that people will pay you for it. That if you do what you love no matter what others may say, and if you work at it hard enough, and long enough, eventually people will recognize it and...

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Explaining real-time predictive analytics with big data (video)

May 6, 2013
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In my presentation to the Strata Santa Clara 2013 conference earlier this year, my goal was to give a succinct (under 20 minutes!) explanation of three terms that are two often used as mere buzzwords: predictive analytics, real time, and big data. You can download the slides for my presentation, Real-time Big Data Analytics: From Deployment to Production, from...

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Veterinary Epidemiologic Research: Count and Rate Data – Zero Counts

May 6, 2013
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Veterinary Epidemiologic Research: Count and Rate Data – Zero Counts

Continuing on the examples from the book Veterinary Epidemiologic Research, we look today at modelling count when the count of zeros may be higher or lower than expected from a Poisson or negative binomial distribution. When there’s an excess of zero counts, you can fit either a zero-inflated model or a hurdle model. If zero

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When the “reorder” function just isn’t good enough…

May 6, 2013
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When the “reorder” function just isn’t good enough…

The reorder function, in R 3.0.0, is behaving strangely (or I’m really not understanding something).  Take the following simple data frame: df = data.frame(a1 = c(4,1,1,3,2,4,2), a2 = c(“h”,”j”,”j”,”e”,”c”,”h”,”c”)) I expect that if I call the reorder function on the … Continue reading →

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Oracle R Distribution for R 2.15.2 available on public-yum

May 6, 2013
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Oracle R Distribution for R 2.15.2 available on public-yum

Oracle R Distribution (ORD) for R 2.15.2 on Linux is now available for download from Oracle's public-yum repository.  R 2.15.2 is a maintenance update that includes improved performance and reduced memory usage for some commonly-used functions, increased memory available for data on 64-bit systems, enhanced localization for Polish language users, and a number of bug fixes.  Detailed updates...

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Bayesian and Frequentist Approaches: Ask the Right Question

May 6, 2013
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Bayesian and Frequentist Approaches: Ask the Right Question

It occurred to us recently that we don’t have any articles about Bayesian approaches to statistics here. I’m not going to get into the “Bayesian versus Frequentist” war; in my opinion, which style of approach to use is less about philosophy, and more about figuring out the best way to answer a question. Once you Related posts:

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Incomplete Data by Design: Bringing Machine Learning to Marketing Research

May 6, 2013
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Incomplete Data by Design: Bringing Machine Learning to Marketing Research

Survey research deals with the problem of question wording by always asking the same question.  Thus, the Gallup Daily Tracking is filled with examples of moving averages for the exact same question asked precisely the same way every day. &nb...

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New fixed.angle() Function

Hello morphometricians,Below you can find a new fixed angle function addressing the problem discovered by Fabio Machado in the morphmet mail archive. We will include this function in our next schedule update to geomorph. Cheers, Erik CODE: ...

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Mixed Model Example — Wagner et al. (2006)

May 6, 2013
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Mixed Model Example — Wagner et al. (2006)

I am preparing for a workshop on mixed models and looked at the paper “Accounting for multilevel data structures in fisheries data using mixed models” by Wagner et al. (2006) (PDF available here).  Wagner et al. (2006) used two examples, with the … Continue reading →

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