Couple of months back I read Jeffrey Breen’s presentation on mining Twitter for consumer attitudes towards airlines, so I was just curious how it would look if I estimate the sentiment toward major hotels. So here it is: # load twitter library __ library(twitteR) # search for all the hilton tweets __ ... [Read more...]

A few friends have asked for self-study resources on learning (or brushing up on) basic statistics. I plan to keep updating this post as I find more good suggestions. Of course the ideal case is to have a good teacher … Continue reading → [Read more...]

The IBM Netezza analytics appliances combine high-capacity storage for Big Data with a massively-parallel processing platform for high-performance computing. With the addition of Revolution R Enterprise for IBM Netezza, you can use the power of the R language to build predictive models on Big Data. In the demonstration below, Revolution ... [Read more...]

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By Yanchang zhao, RDataMining.com Building prediction/classification models is one of the most widely-seen data mining tasks in business applications. To share experience on building prediction models with R, I have started a discussion at RDataMining group on LinkedIn with the … Continue reading → [Read more...]

Firstly, I know nothing about election fraud – this isn’t a serious post. But, I do like to do some simple coding. Ben Goldacre posted on using Benford’s Law to look for evidence of Russian election fraud. Then Richie Cotton did the same, but using R. Commenters on both ... [Read more...]

There has been some discussion about whether Google Scholar or one of the proprietary software companies numbers are better for citation counts. I personally think Google Scholar is better for a number of reasons: Higher numbers, but consistently/a... [Read more...]

It has been a strange last ten days since we unexpectedly entered grant writing mode. I was looking forward to work on this issue near the end of the year but a likely change on funding agency priorities requires applying … Continue reading → [Read more...]

In this article, I show you how to create a data.frame from a text submitted in a textarea field with FastRWeb. Requirements FastRWeb installed Knowledge of webforms ?read.table Experience in HTML5 Submit This example needs two scripts. The first one contains the webform. I wrote a FastRWeb script ... [Read more...]

Labelling a graphics panel in R is easy right? Sure it is, just use text and define the coordinates. text(x=5, y=10, "a") But is there an easy way to get in the same place all the time, even if you have different axis lengths (e.g. 0 to 5 on the ... [Read more...]

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This video tutorial demonstrates how to import data into R that is currently in SPSS format. The video also shows how to do use a few basic commands on datasets, once they are imported into R. The steps in this video apply whether you are using a Mac or a ... [Read more...]

If I google for “probability distribution” I find the following extremely bad picture: It’s bad because it conflates ideas and oversimplifies how variable probability distributions can generally be. Most distributions are not unimodal. Most dist... [Read more...]

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For the longest time I resisted customizing R for my particular environment. My philosophy has been that each R script for each separate analysis I do should be self contained such that I can rerun the script from top to bottom on any machine and get the same results. This ... [Read more...]

It's been a while since I have posted here. I have been swamped with some papers I am trying to get out, finishing up the dissertation, and interviews (faculty ones in addition to others). I should have some big news in the next couple of weeks regar... [Read more...]

While playing around with Bayesian methods for random effects models, it occured to me that inverse-Wishart priors can really bite you in the bum. Inverse Wishart-priors are popular priors over covariance functions. People like them priors because they are conjugate to a Gaussian likelihood, i.e, if you have data ... [Read more...]

With 1.2 under our belts, we go now to the example in section 1.3 which was designed to show us how to partition a larger set of data into subsets for analysis. In this case, we’re going to jump to example 1.3.2 to determine the number of live births. While the Python ... [Read more...]

RcppArmadillo release 0..2.36 is now on CRAN. It contains just the changes from the new Armadillo release 2.4.4. The NEWS entry below summarises the changes. 0.2.36 2012-03-05 o Upgraded to Armadillo release 2.4.4 * fixes for q... [Read more...]