1515 search results for "regression"

How Google and Facebook are using R

February 19, 2009
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How Google and Facebook are using R

(March 26th Update: Video now available) Last night, I moderated our Bay Area R Users Group kick-off event with a panel discussion entitled “The R and Science of Predictive Analytics”, co-located with the Predictive Analytics World conference here in SF. The panel comprised of four recognized R users from industry: Bo Cowgill, Google Itamar Rosenn,

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R-Sessions 32: Forward.lmer: Basic stepwise function for mixed effects in R

February 13, 2009
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Intended to be a customized solution, it may have grown to be a little more. forward.lmer is an early installment of a full stepwise function for mixed effects regression models in R-Project. I may put in some work to extend it, or I may not. Neverthel...

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Fitting Legendre (orthogonal) polynomials in R

February 10, 2009
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Fitting Legendre (orthogonal) polynomials in R

Frederick Novomestky packaged a series of orthogonal polynomials in the orthopolynom R package. However, his functions can not be used "directly" in a statistical model, say in lm(). There is no need to use functions from orthopolynom package, since th...

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A Handbook of Statistical Analyses Using R – Everitt and Hothorn (2006)

January 31, 2009
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Title: A Handbook of Statistical Analyses Using RAuthor(s): Brian S. Torvitt; Torsten HothornPublisher/Date: Chapman & Hall/2006Statistics level: Intermediate to advancedProgramming level: Intermediate Overall recommendation: Highly recommended ...

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MCMCglmm package for R

January 29, 2009
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MCMCglmm package for R

Jarrod Hadfield published MCMCglmm package on CRAN. The package can fit generalised linear mixed models via MCMC methods. Bellow is the abstract from the vignette. The list of supported models is quite impressive. Nice job Jarrod! This is not the first...

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R: Combining vectors or data frames of unequal length into one data frame

January 23, 2009
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R: Combining vectors or data frames of unequal length into one data frame

Today I will treat a problem I encounter every once in a while. Let’s suppose we have several dataframes or vectors of unequel length but with partly matching column names,  just like the following ones: df1 <- data.frame(Intercept = .4, x1=.4, x2=.2, x3=.7) df2 <- data.frame(Intercept = .5,        x2=.8       ) This for example may occur when fitting several

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R resources for psychologists

January 12, 2009
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R resources for psychologists

As a quick follow-up to my previous post, I'll quickly note some R links specifically aimed at psychologists. Jonathan Baron and Yuelin Li have a excellent set of notes that cover ground from R basics to ANOVA (including repeated measures ANOVA) and beyond. Jonathan Baron also maintains a general set of R links. William Revelle's R guide for...

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Multiseat setup via Userful

January 3, 2009
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As I had blogged a while back, multiseat use broke following the normal upgrade to Ubuntu 8.10. I had also suggested a fix but it turns out that the fix didn't work. So we had a clear regression -- multiseat use of a single Ubuntu workstation with two screens, two keyboards and two mice no longer worked. Consequently, the kids ended...

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Modeling Financial Time Series with S-PLUS

November 12, 2008
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Although S-plus is the most terrible language I have ever used in terms of debugging (I have to say that, no offense to S-plus fans, as my colleagues said, it is hard to understand it is still existed in 21 centuary), I found the S-plus scripts accomp...

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How to Recover the Missing X(1) for the USL Scalability Model

July 29, 2008
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How to Recover the Missing X(1) for the USL Scalability Model

When it comes to assessing application scalability, controlled measurements of the type that can be obtained with tools like Grinder or LoadRunner, are very useful because they provide a direct measurement of the throughput, X(N), as a function of the...

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