2967 search results for "GIS"

Pollination effectiveness landscape

February 28, 2013
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Pollination effectiveness landscape

I want to show you a pollination landscape, but this is not a pollinator landscape with flowers and nesting sites, but a plot showing two components of pollination. Quantity and quality. A recent paper by Pedro Jordano (see here for other … Continue reading →

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Classifying Emails as Spam or Ham using RTextTools

February 28, 2013
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Recently, I had read an article on R-bloggers, titled Classifying Breast Cancer as Benign or Malignent using RTextTools by Timothy P. Jurka, who is the author of both that article and the RTextTools package. Having reproduced the results using the...

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Workshops on Modelling Choices using R in Toronto

February 27, 2013
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Making choices is inherently human. We choose between brands of cereal or amongst candidates in an election. At times, choices may be influenced by the characteristics of the decision maker, such as age, income and sex. Choices may also be influenced by the attributes of competing alternatives, such as the cost of travelling between two cities by air or...

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UPDATE Multiple postgreSQL Table Records in Parellel

February 27, 2013
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UPDATE Multiple postgreSQL Table Records in Parellel

Unfortunately the RpostgreSQL package (I’m pretty sure other SQL DBs as well) doesn’t have a provision to UPDATE multiple records (say a whole data.frame) at once or allow placeholders making the UPDATE a one row at a time ordeal, so I built a work around hack to do the job in parellel.  The big problem

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How to make a scientific result disappear

February 27, 2013
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How to make a scientific result disappear

Nathan Danneman (a co-author and one of my graduate students from Emory) recently sent me a New Yorker article from 2010 about the “decline effect,” the tendency for initially promising scientific results to get smaller upon replication. Wikipedia can summarize the phenomenon as well as I can: In his article, Lehrer gives several examples where

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How to make a scientific result disappear

February 27, 2013
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How to make a scientific result disappear

Nathan Danneman (a co-author and one of my graduate students from Emory) recently sent me a New Yorker article from 2010 about the “decline effect,” the tendency for initially promising scientific results to get smaller upon replication. Wikipedia can summarize the phenomenon as well as I can: In his article, Lehrer gives several examples where

Read more »

Course: Statistical Practice in Epidemiology with R

February 25, 2013
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Course: Statistical Practice in Epidemiology with R

Statistical Practice in Epidemiology with R is a one week course aimed at promoting the use of R among epidemiologists. This annual course has been running almost every year since 2004. This year, the course will take place from 23 … Continue reading →

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Reproducible research with R, Knitr, Pandoc and Word

February 25, 2013
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Add references and a style sheet Below I briefly outline why Pandoc is an essential part of my research workflow, and demonstrate how to seamlessly integrate it with a bibliographic system and code written in R to produce high quality word or pdf documents. I also...

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the BUGS Book [guest post]

February 24, 2013
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the BUGS Book [guest post]

(My colleague Jean-Louis Fouley, now at I3M, Montpellier, kindly agreed to write a review on the BUGS book for CHANCE. Here is the review, en avant-première! Watch out, it is fairly long and exhaustive! References will be available in the published version. The additions of book covers with BUGS in the title and of the corresponding

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Large correlation in parallel

February 24, 2013
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Large correlation in parallel

A little improvement to the bigcor function proposed on Rmazing to compute huge correlation matrix in R, I made the function work in parallel using all the CPU cores available on the machine. The code is here.Here is a benchmark of the 2 func...

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