Google AI Challenge: Scores/Rank by Language

December 8, 2010
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Google AI Challenge: Scores/Rank by Language

A quick follow up to the previous post: about the the scores in the 2010 Google AI competition relative to programming language.  The chart above makes each language visible and discrete - and the scales are the same.library(ggplot2)df<- read.c...

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Google AI Challenge: Scores/Rank by Language

December 8, 2010
By
Google AI Challenge: Scores/Rank by Language

A quick follow up to the previous post: about the the scores in the 2010 Google AI competition relative to programming language.  The chart above makes each language visible and discrete - and the scales are the same.library(ggplot2)df<- read.c...

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inline 0.3.8

December 7, 2010
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Romain pushed verion 0.3.8 of inline to CRAN earlier today, and I just updated the Debian package. This version adds an internal performance enhancement which is obtained by making due with fewer reads. The short NEWS file entry follows: 0.3.8 2...

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Big Data Logistic Regression with R and ODBC

December 7, 2010
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Big Data Logistic Regression with R and ODBC

Recently I've been doing a lot of work with predictive models using logistic regression.  Logistic regression is great for determing probable outcomes of a independent binary target variable.  R is a great tool for accomplishing this task.&nb...

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Big Data Logistic Regression with R and ODBC

December 7, 2010
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Big Data Logistic Regression with R and ODBC

Recently I've been doing a lot of work with predictive models using logistic regression.  Logistic regression is great for determing probable outcomes of a independent binary target variable.  R is a great tool for accomplishing this task.&nb...

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R Workflow

December 7, 2010
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R Workflow

When working with R you end up using a large number of datasets, packages, functions, objects, output files, workspaces, etc.  It can get a bit overwhelming trying to keep everything organized.  That is why a consistent, well-organized workf...

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Bayesian model selection

December 7, 2010
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Bayesian model selection

Last week, I received a box of books from the International Statistical Review, for reviewing them. I thus grabbed the one whose title was most appealing to me, namely Bayesian Model Selection and Statistical Modeling by Tomohiro Ando. I am indeed interested in both the nature of testing hypotheses or more accurately of assessing models,

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Build RQuantLib on 32-bit Windows

December 7, 2010
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Before you start, note that there is now a Windows binary of RQuantLib is available on CRAN.Due to a change in how R-2.12.0 is built, CRAN maintainers could no longer provide a Windows binary of RQuantLib with the QuantLib library they had been using....

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Build RQuantLib on 32-bit Windows

December 7, 2010
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Before you start, note that there is now a Windows binary of RQuantLib is available on CRAN.Due to a change in how R-2.12.0 is built, CRAN maintainers could no longer provide a Windows binary of RQuantLib with the QuantLib library they had been using....

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Finding roots of functions in actuarial science

December 7, 2010
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Finding roots of functions in actuarial science

The following simple code can be used to find roots of functions (based on the secant algorithm), secant=function(fun, x0, x1, tolerence=1e-07, niter=500){for ( i in 1:niter ) { x2 <- x1-fun(x1)*(x1-x0)/(fun(x1)-fun(x0)) if (abs(fun(x2)) < to...

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Kendall Rank Coefficient by GPU

December 7, 2010
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Kendall Rank Coefficient by GPU

The correlation coefficient is a measurement of correlation between two random variables. While its computation is straightforward, it is not readily applicable to non-parametric statistics. read more

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Webinar: Revolution R is 100% R and More

December 7, 2010
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I'll be hosting a webinar tomorrow (Wednesday) aimed at R users who want to know more about how Revolution R Enterprise extends open source R for big data, Web services, multi-core processing, debugging and more. For R users at schools and universities, I'll also explain how you can download and use Revolution R Enterprise free of charge. The full...

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Webinar: Revolution R is 100% R and More

December 7, 2010
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I'll be hosting a webinar tomorrow (Wednesday) aimed at R users who want to know more about how Revolution R Enterprise extends open source R for big data, Web services, multi-core processing, debugging and more. For R users at schools and universities, I'll also explain how you can download and use Revolution R Enterprise free of charge. The full...

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Sequential Line Plots in R

December 7, 2010
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Sequential Line Plots in R

I was trying to create some sequential plots today in R to analyse some MCMC simulations. I found the par(ask=TRUE) command very useful for looking at iterations of individual parameter values. Setting the ask graphical parameter to TRUE (before a … Continue reading →

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Webinar on Revolution R Enterprise

December 7, 2010
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R evangelist David Smith, marketing VP at Revolution R, will be giving a webinar showing off some of the finer features of Revolution R Enterprise - an integrated development environment (IDE) for R that has an enhanced script editor with syntax highli...

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Statistique de l’assurance STT6705V, partie 12 bis

December 7, 2010
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Statistique de l’assurance STT6705V, partie 12 bis

In the previous post (here) discussing forecasts of actuarial quantities, I did not mention much how to forecast the temporal component in the Lee-Carter model. Actually, many things can be done. Consider here some exponential smoothing techniques ...

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Le Monde puzzle [49]

December 7, 2010
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Le Monde puzzle [49]

Here is a quick-and-dirty solution to Le Monde puzzle posted a few days ago: the R code counts the number of winning tickets between 1 and N, and stops when there is a proportion of 10% of winning tickets. #winning ticket win=function(n){ #decimal digits decomposition x=rep(0,4) x=n%%10 m=(n-x)/10 x=m%%10 m=(m-x)/10 x=m%%10 m=(m-x)/10 x=m%%10 tic=0 for

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highlight 0.2-5

December 7, 2010
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I pushed highlight 0.2-5 on CRAN. This release improves the latex renderer and the sweave driver so that multiple lines character strings are properly rendered. This example vignette shows it: \documentclass{report} \begin{document} <<echo=FALSE,results=hide>>= old.op <- options( prompt = " ", continue = " " ) @ <<>>= require( inline ) require( Rcpp ) convolve <- cxxfunction( signature( a = "numeric", b...

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R 2.12.1 scheduled for December 16

December 6, 2010
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The next update to R will be a patch release: R 2.12.1 will be released on December 16, as announced today by the R Core Team. As is typical for a patch release, this version will include some minor bug fixes plus a few new features (from the current build's NEWS file): The DVI/PDF reference manual now includes the...

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R 2.12.1 scheduled for December 16

December 6, 2010
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The next update to R will be a patch release: R 2.12.1 will be released on December 16, as announced today by the R Core Team. As is typical for a patch release, this version will include some minor bug fixes plus a few new features (from the current build's NEWS file): The DVI/PDF reference manual now includes the...

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Jeromy Anglim on Reproducible Research and R

December 6, 2010
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Jeromy Anglim, fellow social scientist and R aficionado from across the globe, gave a great talk to the Melbourne R Users Group last week on the joys of creating reproducible results. A subject near and dear to me, but not one that is given enough attention in research training. Jeromy discusses tools for generating reproducible

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What my R code looks and feels like (Vanilla)

December 6, 2010
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Geoff Robinson discusses how to write simple and reusable R code. He provides several examples with code.

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Reproducible Research and R Workflow

December 6, 2010
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Jeromy Anglim discusses best practices and tools used to support reproducible research in R. He discusses tools for R scripting and version control; and provides examples of SWeave. This presentation was given to the Melbourne R Users Group (MelbURN)...

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3 weak days in a row

December 6, 2010
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3 weak days in a row

Recently, Trading the odds posted one of many flavors of mean reverting strategies and I decided to get my hands dirty by writing R code and testing it. You can find full description of the strategy by following latter link above. Long story short – if SPY shows lower open, high and close 3 days in

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JAGS – Bayesian Analysis

December 6, 2010
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JAGS – Bayesian Analysis

JAGS is used for Bayesian analysis using MCMC and stands for Just Another Gibbs Sampler.  It is an alternative to WinBUGS and can be accessed through R just like WinBUGS (via R2jags or RJags).  It will work on a Mac unlike WinBUGS.  The ...

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Using the "Divide by 4 Rule" to Interpret Logistic Regression Coefficients

December 6, 2010
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I was recently reading a bit about logistic regression in a book on hierarchical/multilevel modeling when I first learned about the "divide by 4 rule" for quickly interpreting coefficients in a logistic regression model in terms of the predicted probabilities of the outcome. The idea is pretty simple. The logistic curve (predicted probabilities) is steepest at the center where...

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Example 8.17: Logistic regression via MCMC

December 6, 2010
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Example 8.17: Logistic regression via MCMC

In examples 8.15 and 8.16 we considered Firth logistic regression and exact logistic regression as ways around the problem of separation, often encountered in logistic regression. (Re-cap: Separation happens when all the observations in a category sha...

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Electoral Marimekko Plots

December 6, 2010
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Electoral Marimekko Plots

To be reductive, visual displays of quantitative information might be reasonably categorized on a continuum between “data display” and “statistical graphics.” By statistical graphics, I mean a plot that displays some summary of or relationship amongst several variables, likely having undergone some processing or analysis. This may be as simple as a scatterplot of a … Continue reading →

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Bear hunting

December 6, 2010
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Bear hunting

When were there bear and bull markets in US stocks since 1950? Smoothing While we’d really like to estimate the expected return at each point in time, finding bear markets is ambitious enough.  The plan starts by smoothing the daily returns through time, as in Figure 1. Figure 1: Smoothed returns with a 4 year … Continue reading...

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