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Familiar with R and DataVis? Take a try in PISA data visualisation contest for useR2014 participants.
There are two contest tracks. In each you can win 700\$.

The prizes are funded by The Organisation for Economic Co-operation and Development (OECD) and tracks are related to data from The Programme for International Student Assessment (PISA).

Note that the deadline is Sunday 29 june 2014 Pacific Daylight Time.

Below you can find an simple example how to read PISA data and plot some basic graphs.

Let’s see in which countries pupils have high average reading + math score and in which countries pupils are on average better in math than reading.

``` library(ggplot2) # read students data from PISA 2012 # directly from URL con <- url("http://beta.icm.edu.pl/PISAcontest/data/student2012.rda") load(con) # calculate weighted mean from math / reading scores # W_FSTUWT stands for final weights mathScores <- unclass(by(student2012[,c("PV1MATH", "W_FSTUWT")], student2012\$CNT, function(x) weighted.mean(x[,1], x[,2])) ) readScores <- unclass(by(student2012[,c("PV1READ", "W_FSTUWT")], student2012\$CNT, function(x) weighted.mean(x[,1], x[,2])) ) # create a data.frame with scores and country names # remove names with ( in name) readMathScores <- data.frame(Country=names(readScores), readScores, mathScores) readMathScores <- readMathScores[-grep(readMathScores\$Country, pattern="(", fixed=TRUE),]   ggplot(readMathScores, aes(x=mathScores + readScores, y = mathScores - readScores, label = Country)) + geom_text() + theme_bw() ``` Let’s add country sizes to the plot.

``` sizeScores <- unclass(by(student2012[,"W_FSTUWT"], student2012\$CNT, sum) ) # create a data.frame with scores, sizes and country names # remove names with ( in name) readMathScores <- data.frame(Country=names(readScores), readScores, mathScores, sizeScores) readMathScores <- readMathScores[-grep(readMathScores\$Country, pattern="(", fixed=TRUE),]   ggplot(readMathScores, aes(x=mathScores + readScores, y = mathScores - readScores, label = Country, size = sqrt(sizeScores))) + geom_text() + theme_bw() + theme(legend.position="none") ``` I am very eager to see winning submissions.