www.finn.no is the most popular website in Norway. It supplies a lot of features, such as booking flight tickets, finding job, renting and sales of houses, cars and other properties, etc. I just have some experience with it. I sold and bought cars, apartment and some other stuff. ... [Read more...]

SMACOF stands for “Scaling by MAjorizing a COmplicated Function,” and it is a multidimensional scaling algorithm for metric unfolding of, among other things, rectangular ratings matrices. One neat Political Science application of MDS is i... [Read more...]

[of interest mostly to French and R bilinguals] La prochaine édition des Rencontres R aura lieu à Lyon en Juillet prochain. Ci-dessous, l’appel officiel à contributions. ————————————————– Appel à communication des 2èmes Rencontres R : Dans la lignée de la conférence internationale Use’R et suite à la première édition qui a ... [Read more...]

Consider the following "magic" 3-gon ring, filled with the numbers 1 to 6, and each line adding to nine. Working clockwise, and starting from the group of three with the numerically lowest external node (4,3,2 in this example), each solution can be described uniquely. For example, the above solution can be described by ... [Read more...]

Now that I’m done with finals, I finally have time to update my blog. I managed to find three separate Wikipedia entries: one about the Quality of Life Scores of several different countries, one about the number of Nobel Laureates per capita, and one that is a List of ... [Read more...]

I wanted to thank those of you who have emailed and commented on my last post and its Link to Item Response Theory Presentations Using R.  In the Psychometrics Centre website, it is not until Topic 7 called Unidimensional IRT models for binar... [Read more...]

By way of following up on an old in-joke, and doing something constructive because I couldn’t get to sleep, I thought I would revisit the Flag Space plot that I blogged about a while back and learn how to do it. … Continue reading → [Read more...]

Coursera's Computing for Data Analysis course on R is now over, with four weeks of free, in-depth training on the R language. While you'll have to wait for the next installment of the course to participate in the full online learning experience, you can still view the lecture videos, courtesy ... [Read more...]

Statistical plots drawn with the ggplot2 package generate numerous grid grobs and viewports which are labelled and organised into a coherent hierarchy. This report describes an example that shows how to manipulate the grobs and viewports in a ggplot2 plot … Continue reading → [Read more...]

Note: probably of interest only to the intersection of the readers who are into niche music genres and those interested in network visualization. My music interests have always been rather, hmm…, eclectic. Somehow IDM, ambient, darkwave, triphop, acid jazz, bossa … Continue reading → [Read more...]

Recently I’ve been working on some jackknife and bootstrapping problems.  While working on those projects I figured it would be a fun distraction to take the process and estimate pi.  I’m sure this problem has been tackled countless times but I have never bothered to try it using ... [Read more...]

Redos of the plots from this post: Bit more communicative, though the overplotting is a bit annoying. Code: ## gis libraries library(spBayes) library(MBA) library(geoR) library(fields) library(sp) library(maptools) library(rgdal) library(classInt) library(lattice) library(xtable) library(spatstat) library(splancs)   ## Other packages library(ggplot2) library(foreign) ... [Read more...]

Source: 1500 random tweets from today with the terms 'gmail down' (pulled from API). [Read more...]

Estimating a least squares linear regression model with fixed effects is a common task in applied econometrics, especially with panel data. For example, one might have a panel of countries and want to control for fixed country factors. In this case the researcher will effectively include this fixed identifier as ... [Read more...]

By default when you start R, T and F are defined as TRUE and FALSE. When I review other people’s code, I often see functions defined with arguments set to these values by default. This is a very bad idea. … Continue reading → [Read more...]

Today’s short post will show how to make a simple map using map_data(). Let’s assume you have data in a CSV file that may look like this: Notice the lower case state names; they will make merging the data much easier. The variable of inte... [Read more...]

R has various facilities for string manipulation including the strsplit function to divide a string into substrings based on matching to another string. A simple example is shown below __ strsplit("Stuff", "" [3] "a href=\"/path/test.html\" target=\"\" title=\"An Object\" class=\"myObject\"__Stuff" [4] "/a__" [5] "/td__" […] [Read more...]

Last week I attended a seminar where a talk was given about the economic opportunities in the SAAAME (South-America, Asia, Africa and Middle East) regions. Of course a map was shown with those regions highlighted. The map was not that disimilar to the one below.

library(RColorBrewer)<br>library(rworldmap)<br>data(countryExData)<br>par(mai=c(0,0,0.2,0),xaxs="i",yaxs="i")<br>mapByRegion( countryExData, <br>             nameDataColumn="GDP_capita.MRYA",<br>             joinCode="ISO3", nameJoinColumn="ISO3V10",<br>             regionType="Stern", mapTitle=" ", addLegend=FALSE,<br>             FUN="mean", colourPalette=brewer.pal(6, "Blues"))

It is a map ... [Read more...]

This is my new website! It’s built using jekyll-bootstrap and hosted on Github. [Read more...]

The other day I was trying to set up an R for Windows installation on a USB drive. As I don't have a Windows machine, I had to use the university computer to do this task. However, for some reason, they've blocked R from downloading and installing pack... [Read more...]