I posted earlier this week about sofa (here), introducing a package I started recently that interacts with CouchDB from R. There's been a fair amount of response at least in terms of page views, so I'll take that as a sign to keep going. One thing that would be nice ... [Read more...]

This post introduces a new R package named PISA2009lite. I will show how to install this package, what is inside and how to use it. Introduction PISA (Programme for International Student Assessment) is a worldwide study focused on measuring performance of 15-year-old school pupils. More precisely, scholastic performance on ... [Read more...]

In Chapter 18, we discuss a relatively new method for measuring predictor importance called the maximal information coefficient (MIC). The original paper is by Reshef at al (2011). A summary of the initial reactions to the MIC are Speed and Tibshirani (and others can be found here). My (minor) beef with it ... [Read more...]

The Sydney Users of R Forum (SURF) will be hosting me for a talk on July 10. The focus will be Rcpp for R and C++ integration, and the intent is to have this be really applied with lots of motivating examples. Organizers Louise and Eugene were able... [Read more...]

I wrote a couple days about about importing Excel files into R. There are lots of ways to do this, but all the ways that use only R have drawbacks (as I outlined in my last post), and all the other ways require installation of programs other than R. I’... [Read more...]

The next LondonR meeting takes place on the 16 July and registrations have already exceeded 200. Presentations at the meeting will be made by Rich Pugh of Mango Solutions, [Read more...]

American Century Investments is a top-20 mutual fund company with more than 125 billion dollars of assets under management. The quantitative investment group manages 22 funds, and takes an objective, systematic and disciplined approach to determine which stocks to buy and sell. Real-time data and carefully calibrated statistical models are the foundation ... [Read more...]

So it seems like it’s that time of year when the Guardian publish their university rankings data (Datablog: University guide 2014), which means another opportunity to have a tinker and see what I’ve learned since last year… (Last year’s hack was a Filtering Guardian University Data Every Which ... [Read more...]

Anscombe’s quartet is a collection of four datasets that look radically different yet result in the same regression line when using ordinary least square regression. The graph below shows Anscombe’s quartet with imposed regression lines (taken from the Wikipedia article). While least square regression is a good choice ... [Read more...]

The age of "blockbuster drugs" is coming to an end, as personalized medicine becomes a reality. Data science will be a major driver of innovation in these and other areas of the pharmaceutical industry. This was demonstrated during a project the Data Science Labs team executed on with a major ... [Read more...]

In this blog post, I would walk you through the steps from downloading to installing the RGoogleAnalytics package on your machine. The RGoogleAnalytics package currently resides at https://code.google.com/p/r-google-analytics/ and this page lists the latest developments around the package. The zip and tarball archives for the ... [Read more...]

[This article was first published on geomorph, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on [Read more...]

Two of my favorite functions are copy.table() and paste.table(). I’m going to turn this story on its head and give you the ending first. The first allows you to copy a data frame to the clipboard in a format that … Continue reading → [Read more...]

[This article was first published on - R, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on [Read more...]

I have previously discussed instrumental variables (hereand here)  from a somewhat technical standpoint, but now I’d like to present a very basic example with a toy data set that demonstrates how IV estimation works in practice. The data set below is fabricated for demonstration purposes. The idea is to ... [Read more...]

by Joseph Rickert The basic way to plot a classification or regression tree built with R’s rpart() function is just to call plot. However, in general, the results just aren’t pretty. As it turns out, for some time now there has been a better way to plot rpart() ... [Read more...]

A short tutorial for spatial overlays using R-GIS..library(sp)library(dismo)# spatial dataalt gadm # viewplot(alt)plot(gadm, add=T)# some addressespts # make it spatialcoords spdf_pts # assign CRS/projectionproj4string(spdf_pts) # check datastr(spdf_pts)# plot it on topplot(spdf_pts, cex = 2, col = 2, add = T)# do an ... [Read more...]

Before you begin, be aware that there is others excellent posts about the issue, as: 1. Compiling 64-bit R 2.10.1 with MKL in Linux 2. Speeding up R with Intel’s Math Kernel Library (MKL) 3. Performance benefits of linking R to multithreaded math libraries 4. Using MKL-Linked R in Eclipse But, as recently i ... [Read more...]

[caption id="attachment_749" align="aligncenter" width="504"] A transition between states - the above is a simulation of before and after surgery where I've highlighted the large proportion that doesn't improve in the moderate group.[/caption] As an orthopaedic surgeon I'm often interested in how a patient is doing after surgery ... [Read more...]

Yield Curve fitting - the Smith-Wilson method Yield Curve fitting - the Smith-Wilson method This article illustrates the R package SmithWilsonYieldCurve, and provides some additional background on yield curve fitting. The method implemented in the package fits a curve to interest rate market data such that the observed prices of ... [Read more...]