Veterinary Epidemiologic Research: Modelling Survival Data – Non-Parametric Analyses

May 23, 2013
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Veterinary Epidemiologic Research: Modelling Survival Data – Non-Parametric Analyses

Next topic from Veterinary Epidemiologic Research: chapter 19, modelling survival data. We start with non-parametric analyses where we make no assumptions about either the distribution of survival times or the functional form of the relationship between a predictor and survival. There are 3 non-parametric methods to describe time-to-event data: actuarial life tables, Kaplan-Meier method, and

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The R-Podcast Episode 13: Interview with Yihui Xie

May 23, 2013
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It’s an episode of firsts on the R-Podcast! In this episode recorded on location I had the honor and privilege of interviewing Yihui Xie, author of many innovative packages...

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Vote in the KDnuggets poll on Analytics Software

May 22, 2013
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The 14th annual KDnuggets poll measuring use of analytics software is open for voting. The poll asks, "What Predictive Analytics, Big Data, Data mining, Data Science software you used...

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How Important is Variable Selection?

May 22, 2013
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How Important is Variable Selection?

Very. If you have 10 possible independent regressors, and none of which matter, you have a good chance to find at least one is important. A good chance being...

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Operating on files with R: copy and rename

Nowadays, routinary operations on files, such as renaming or copying, are performed with some mouse clicks. Sometimes, it is useful perform this operations in batch. Linux users perform this...

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What happened to six million voters?

May 22, 2013
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What happened to six million voters?

The recent elections in Pakistan on May 11 were a great success by all means. In spite of the threats for violence by Al-Qaeda and its local franchises in...

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My Prime Sieve – Homage to Yitan Zhang

May 22, 2013
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My Prime Sieve – Homage to Yitan Zhang

# As a homage to Yitang Zhang who has proven a mind-bending property of Prime Pairs, I have written a prime Sieve to detect all of the prime numbers from...

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Video: R, ProjectTemplate, RStudio and GitHub: Automate the boring bits and get on with the fun stuff

May 22, 2013
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This post shares the video from the talk presented on 15th May 2013 by Dr Kendra Vant on ProjectTemplate, github and Rstudio at Melbourne R Users. Overview: Want to...

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Get your questions answered about Open Data

May 21, 2013
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The OpenData StackExchange site has just launched in beta, and looks to be a great resource for open data sources. Like StackOverflow for programming and CrossValidated for statistics, OpenData...

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Getting to the point – an alternative to the bezier arrow

May 21, 2013
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Getting to the point – an alternative to the bezier arrow

(This article was first published on G-Forge » R, and kindly contributed to R-bloggers) An alternative bezier arrow to the regular grid-bezier. Apart from a cool gradient it has...

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Spatial correlograms in R: a mini overview

May 21, 2013
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Spatial correlograms in R: a mini overview

Spatial correlograms are great to examine patterns of spatial autocorrelation in your data or model residuals. They show how correlated are pairs of spatial observations when you increase the...

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Slide: one function for lag/lead variables in data frames, including time-series cross-sectional data

May 21, 2013
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I often want to quickly create a lag or lead variable in an R data frame. Sometimes I also want to create the lag or lead variable for different...

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An R debugging example

May 21, 2013
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The steps taken to fix an R problem. Task To prepare for the Portfolio Probe blog post called “Implied alpha and minimum variance”, I tried to update a matrix...

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R programming challenge: Escape the zombie horde

May 20, 2013
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R programming challenge: Escape the zombie horde

So when the world is taken over by a Zombie horde, you're going to want to figure out a way to get the human population to safety. This R...

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Solving Multiple Supplier Selection Problem using R and LP Solve

May 20, 2013
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Solving Multiple Supplier Selection Problem using R and LP Solve

(This article was first published on Enterprise Software Doesn't Have to Suck, and kindly contributed to R-bloggers) To leave a comment for the author, please follow the link and...

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R 3.0.1 is released

May 20, 2013
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R 3.0.1 is released

R 3.0.1 (codename “Good Sport”) was released last week. As mentioned earlier by David, this version improves serialization performance with big objects, improves reliability for parallel programming and fixes...

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Non-Verbal Reasoning Test – Concerto

May 20, 2013
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Non-Verbal Reasoning Test – Concerto

I have just released my first complete test of non-verbal problem solving skills.  It is run on Concerto (an R-based application development platform targeted at primarily test developers)  Try...

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More on Chutes & Ladders

May 20, 2013
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More on Chutes & Ladders

Matt Maenner asked about the sawtooth pattern in the figure in my last post on Chutes & Ladders. Damn you, Matt! I thought I was done with this. Don’t...

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Model fitting exam problem

May 20, 2013
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Recently I have run an exam where the following question had risen many problems for students (here I give its shortened formulation). You are given the data generating process...

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qdap 0.2.2 released

May 20, 2013
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qdap 0.2.2 released

I’m very pleased to announce the release of qdap 0.2.2 This is the third installment of the qdap package available at CRAN. The qdap package automates many of the...

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Implied alpha and minimum variance

May 20, 2013
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Implied alpha and minimum variance

Under the covers of strange bedfellows. Previously The idea of implied alpha was introduced in “Implied alpha — almost wordless”. In a comment to that post Jeff noticed that...

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analyze the new york city housing and vacancy survey (nychvs) with r

May 19, 2013
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for those interested in the real estate and rental markets of the big apple, the census bureau's nyc housing and vacancy survey might be your key to the city. ...

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Geolocate IP addresses in R

May 19, 2013
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Geolocate IP addresses in R

This R function uses the free freegeoip.net geocoding service to resolve an IP address (or a vector of them) into country, region, city, zip, latitude, longitude, area and metro...

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Playing cards in Vegas?

May 19, 2013
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Playing cards in Vegas?

In a previous post, a few weeks ago, I mentioned that I will be in Las Vegas by the end of July. And I took the opportunity to write...

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More tide prediction with R

May 19, 2013
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In the previous post I outlined how to query the XTide software with R and parse the results into a handy-dandy data frame. The biggest hurdle with that method...

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R code to obtain and plot rainfall data for the whole world

If you want to create rainfall maps for the whole world in R there is no readily available code or package to do this. Moreover, data publicly available from...

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Update to PSID panel builder for R: psidR

May 19, 2013
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I just pushed the most recent version of the PSID panel data builder introduced a little while ago. Got some user feedback and made some improvements. The package is...

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R Quick Tip: Shutdown Windows after Script Has Finished

May 19, 2013
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Quite often I have long procedures running and want to do this over night. However, my computer would still be running all night after the script has finished. This...

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Sharing my R notes

May 18, 2013
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Sharing my R notes

I started working with R 2 1/2 years ago. I remember opening R closing it and thinking it was the dumbest thing ever (command line to a non programmer...

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