Cluster analysis is widely applied in data analysis. Obviously hierarchical clustering is the simple and important method to do clustering. In brief, hierarchical clustering methods use the elements of a proximity matrix to generate a tree diagram or dendogram. From the tree diagram, we can draw our own conclusions about ... [Read more...]

Last year I taught an online course on forecasting using R. The slides and exercise sheets are now available at www.otexts.org/fpp/resources/ [Read more...]

At work I write a ton of SQL, and I do most of my querying using R.  The workflow goes: Create a string with the SQL in R Plug the string into fetchQuery (see my previous post) This solution works relatively well, but i’m a bit unhappy writing strings ... [Read more...]

RStudio's Hadley Wickham has just introduced a new package for filtering, selecting, restructuring and aggregating tabular data in R: the dplyr package. It's similar in concept to Hadley's original plyr package from 2009, but with several key improvements: It works exclusively with data in R data frames; It can process data ... [Read more...]

A friend of mine just alerted me to a story on NPR describing a prize on offer from Warren Buffett and Quicken Loans. The prize is a billion dollars (1B USD) for correctly predicting all 63 games in the men’s Division I college basketball tournament this March. The facebook page ... [Read more...]

Finally I set up my blog website hosted by GitHub Pages. It is quite amazing to create a website totally for free. After some trial and error, now I come up with a stable workflow to publish my work, introductory materials, and random thoughts online. ... [Read more...]

Together with many other packages written by Hadley Wickham, plyr is a package that I use a lot for data processing. The syntax is clean, and it works great for breaking down larger data.frame‘s into smaller summaries. The greatest disadvantage… See more › [Read more...]

This is a short but sweet post on how to create a geojson file in R .  Remember that you can render geojson files in github.   The post How to create a geojson in R appeared first on Jose Gonzalez. [Read more...]

Despite winter rain, I was delighted to head uptown last week to Skills Matter on the old Goswell Road for the first ever London Julia meetup. The first thing I learnt was that Julia’s friends are called Julians. If you … Continue reading → [Read more...]

I first mentioned Coursera about a year ago, when I hired a new analyst in my core. This new hire came in as a very competent Python programmer with a molecular biology and microbial ecology background, but with very little experience in statistics. I got him to take Roger Peng's ... [Read more...]

[Read more...]

With the new Joyent Manta R SDK we're diving into the R community, so we're honored to be included in the R-Bloggers blog here. We hope to have more R and statistics posts there. The packages' author, Dr. Christopher Hogue has been a great addition to... [Read more...]

In preparation for my LondonR talk in March, I am polishing up my CrimeMap (see previous blog post here and here) in my spare time. Thanks to Chris Beeley and Packt, I won a free e-copy of Chris Beeley’s book following his great talk about Shiny web app during ... [Read more...]

Over the last couple of years, I’ve settled into using R an python as my languages of choice for doing stuff: R, because RStudio is a nice environment, I can blend code and text using R markdown and knitr, ggplot2 and Rcharts make generating graphics easy, and reshapers such ... [Read more...]

A bug fix release of Armadillo came out and was turned into a new RcppArmadillo release which is now on CRAN and will go shortly to Debian. The complete list of changes is below. Changes in RcppArmadillo version 0.4.000.2 (2014-01-21) Up... [Read more...]

Introduction R provides functions for both one-dimensional and multi-dimensional optimization. The second topic is much more complicated than the former (see e.g. Nocedal 1999) and will be left for another day. A convenient function for 1D optimization is optimize(), also known as optimise(). Its first argument is a function whose ... [Read more...]

We are looking for a new post-doctoral research fellow to work on the project “Macroeconomic Forecasting in a Big Data World”.  Details are given at the link below jobs.monash.edu.au/jobDetails.asp?sJobIDs=519824 This is a two year position, funded by the Australian Research Council, and working with ... [Read more...]

Choropleth maps are a popular way of representing spatial or geographic data, where a statistic of interest (say, income, voting results or crime rate) are color-coded by region. R includes all of the necessary tools for creating choropleth maps, but Trulia's Ari Lamstein has made the process even easier with ... [Read more...]

Dirk Kroese (from UQ, Brisbane) and Joshua Chen (from ANU, Canberra) just published a book entitled Statistical Modeling and Computation, distributed by Springer-Verlag (I cannot tell which series it is part of from the cover or frontpages…) The book is intended mostly for an undergrad audience (or for graduate students ... [Read more...]

The goal of this open source R-based analysis, as mentioned earlier (first post, second post) is to bring consistency and transparency to the analyses of publicly available Tornado data.The latest addition to the project is the analysis of local t... [Read more...]