A spell-checker in R

February 7, 2012
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A spell-checker in R

I came across Dr. Peter Norvig’s blog about writing a basic spell-checker (http://norvig.com/spell-correct.html), and just had to try to implement it in R. Please excuse the ugly-ish code (I have not optimized it or commented it adequately at this point, but you can get the idea of what it does by reading Dr. Norvig’s blog).

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Two incredibly useful functions to throw into your .rprofile

February 7, 2012
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I’ve neglected this blog for quite some time but I’m getting around to finishing up a bunch of draft posts. But here is a quick one: Listing objects in your global environment A simple ls() doesn’t really tell you enough useful information at a glance. Most often I just want to know what I named

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What’s new in futile.matrix 1.1.2

February 7, 2012
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What’s new in futile.matrix 1.1.2

This is an exciting release of futile.matrix, which in some ways the package grows up and finds its purpose. It …Continue reading »

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updated slides for ABC PhD course

February 7, 2012
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updated slides for ABC PhD course

Over the weekend, I have added a few slides referring to recent papers mentioning the convergence of ABC algorithms, in particular the very relevant paper by Dean et al. I had already discussed in an earlier post. (This is taking a larger chunk of my time than expected! I am glad I will use the

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Example 9.20: visualizing Simpson’s paradox

February 7, 2012
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Example 9.20: visualizing Simpson’s paradox

Simpson's paradox is always amazing to explain to students. What's bad for one group, and bad for another group is good for everyone, if you just collapse over the grouping variable. Unlike many mathematical paradoxes, this arises in a number of real...

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"R": PLS Regression (Gasoline) – 004

February 7, 2012
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"R": PLS Regression (Gasoline) – 004

In the previous post we plot the Cross Validation predictions with:> plot(gas1, ncomp = 3, asp = 1, line = TRUE)We can plot the fitted values instead with:> plot(gas1, ncomp = 3, asp = 1, line = TRUE,which=train) Graphics are different:Of course, using "train" we get  overoptimisc statistics and we should look...

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Gauging Interest in a Montreal R User Group

February 7, 2012
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Gauging Interest in a Montreal R User Group

Some of us over at McGill’s Biology Graduate Student Association have been developing and delivering R/Statistics workshops over the last few years. Through invited graduate students and faculty, we have tackled  everything from multi-part introductory workshops to get your feet wet, to special topics such as GLMs, GAMs, Multi-model inference, Phylogenetic analysis, Bayesian modeling, Meta-analysis,

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What are the most popular bike routes in London?

February 7, 2012
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What are the most popular bike routes in London?

James Cheshire, R user and lecturer at the UCL Centre for Advanced Spatial Analysis, created this map of the most trafficked cycle routes in London: Click to enlarge, it's a gorgeous chart. The bicycle traffic data comes from London's public cycle-hire facility, which currently is only available in central London (which is why you don't see much activity in...

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MAT8886 a short word on profile likelihood

February 7, 2012
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MAT8886 a short word on profile likelihood

Profile likelihood is an interesting theory to visualize and compute confidence interval for estimators (see e.g. Venzon & Moolgavkar (1988)). As we will use is, we will plot But more generally, it is possible to consider where . Then (...

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Early-February flotsam

February 7, 2012
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Early-February flotsam

Mike Croucher at Walking Randomly points out an interesting difference in operator precedence for several mathematical packages to evaluate a simple operation 2^3^4. It is pretty much a divide between Matlab and Excel (does the later qualify as mathematical software?) … Continue reading →

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Update to Partisan Bias in Fed Inflation Forecasts

February 7, 2012
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Update to Partisan Bias in Fed Inflation Forecasts

Since I'm in the depths of PhD thesis revisions I haven't had much time to do much other than update previous posts (see my Stata Country Standardizer Update).Here is an update of an earlier post about possible partisan biases in US Federal Reserve sta...

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Workshop on Mixed and Multilevel Modelling with R in Toronto

February 7, 2012
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Summer Program In Data Analysis (SPIDA): May 24th – June 1st, 2012 In its thirteenth season this year, ISR’s Summer Program in Data Analysis focuses on linear models, beginning with “standard” regression through generalized linear models, and extending to mixed or multilevel models, linear and non-linear and generalized, which incorporate two or more hierarchical levels of data or longitudinal...

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What’s new in futile.paradigm 2.0.4

February 6, 2012
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What’s new in futile.paradigm 2.0.4

Well this certainly took a while but the latest installment of my functional dispatching library for R is finally released …Continue reading »

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how to create a variable with r

February 6, 2012
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(This article was first published on twotorials by anthony damico, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and comment on his blog: twotorials by anthony damico. R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL,...

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how to do simple arithmetic in r

February 6, 2012
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(This article was first published on twotorials by anthony damico, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and comment on his blog: twotorials by anthony damico. R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL,...

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More Beautiful Growth of $1 Chart

February 6, 2012
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More Beautiful Growth of $1 Chart

With all my recent focus on reporting and visualization, you might think that I have the investments all figured out.  Unfortunately, that is not the case, and I will resume more standard investment and systems posts soon.  I did want to shar...

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The anatomy of a Twitter conversation, visualized with R

February 6, 2012
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The anatomy of a Twitter conversation, visualized with R

If you're a Twitter user like me, you're probably familiar with the way that conversations can easily by tracked by following the #hashtag that participants include in the tweets to label the topic. But what causes some topics to take off, and others to die on the vine? Does the use of retweets (copying another users tweet to your...

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General Bayesian estimation using MHadaptive

February 6, 2012
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General Bayesian estimation using MHadaptive

If you can write the likelihood function for your model, MHadaptive will take care of the rest (ie. all that MCMC business). I wrote this R package to simplify the estimation of posterior distributions of arbitrary models. Here’s how it works: 1) Define your model (ie the likelihood * prior). In this example, lets build

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Using apply() to create a unique id

February 6, 2012
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Using apply() to create a unique id

Suppose you have a data set with two identifiers. For example, maybe you're studying the relationships among firms in an industry and you have a way to link the firms to one another. Each firm has an id, but the unique unit in your data set is a pair...

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An R script for estimating future inflation via the Treasury market

February 6, 2012
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One factor that is critical for any financial planning is estimating what future inflation will be. For example, if you’re saving money in an instrument that gains 3% per year, and inflation is estimated to be 4% per year, well then you’re losing m...

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Visualising Activity Around a Twitter Hashtag or Search Term Using R

February 6, 2012
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Visualising Activity Around a Twitter Hashtag or Search Term Using R

I think one of valid criticisms around a lot of the visualisations I post here and on my various #f1datajunkie blogs is that I often don’t post any explanatory context around the visualisations. This is partly a result of the way I use my blog posts in a selfish way to document the evolution of

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The US market will absolutely positively definitely go up in 2012

February 6, 2012
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The US market will absolutely positively definitely go up in 2012

The Super Bowl tells us so. The Super Bowl Indicator The championship of American football decides the direction of the US stock market for  the year.  If a “National” team wins, the market goes up; if an “American” team wins, the market goes down. Yesterday the Giants, a National team, beat the Patriots. The birth … Continue reading...

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googleVis 0.2.14 is released

February 5, 2012
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googleVis 0.2.14 is released

Version 0.2.14 of the googleVis package was released on CRAN today.ChangesThe help files have been checked against changes of the Google Visualisation API, typos in the vignette have been ironed out (thanks to Pat Burns for pointing them out), a new se...

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Comparing correlations update

February 5, 2012
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I have just published R code for calculating CIs for differences between correlations on the Serious stats book blog. This covers independent correlations (taken from chapter 6 of the book) and dependent correlations (new R code written as a suppl...

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Comparing correlations: independent and dependent (overlapping or non-overlapping)

February 5, 2012
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Comparing correlations: independent and dependent (overlapping or non-overlapping)

In Chapter 6 (correlation and covariance) I consider how to construct a confidence interval (CI) for the difference between two independent correlations.  The standard approach uses the Fisher z transformation to deal with boundary effects (the squashing of the distribution and increasing asymmetry as r approaches -1 or 1). As zr is approximately normally distributed

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Rstudio and asreml working together in a mac

February 5, 2012
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December and January were crazy months, with a lot of travel and suddenly I found myself in February working in four parallel projects involving quantitative genetics data analyses. (I’ll write about some of them very soon) Anyhow, as I have … Continue reading →

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RStudio Server part 2: pros of using RStudio server for a remote connection

February 5, 2012
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After playing around with R studio server for a while, I decided to write a followup to my previous blog post. I want to go over a few of the strong points of using RStudio server to access a remote… See more ›

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rjags

February 5, 2012
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Running 64 bit R, JAGS and rjags on EC2 Winbugs and Jags free Item Response Theory from the dot matrix plots of proprietary software and open up a multicoloured world of posterior predictive model checking. Fitting IRT models using brute force is not ...

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Influential People in the "Big Data" Field

February 4, 2012
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Yesterday, Haydn Shaughnnessy wrote a piece for Forbes titled, Who are the Top 20 Influencers in Big Data?Fans of R will be delighted to see David Smith of Revolution Analytics up there at number 2!Congratulations!© 2012, David E. Giles

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