Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.
I hope you have already heard about DataVis contest at useR!2014 (in case you did not, here is more information: http://www.oecd.org/pisa/pisaproducts/datavisualizationcontest.htm).
As a jury member I am not going to submit any work, but I am going to encourage you to play with the data, crunch a finding and submit interesting plot.
How easy is to download the data and create some graph?
Let’s take a look at students’ answers for questions: ‘Do you feel happy at school?’ and ‘How familiar are you with Declarative Fractions?’.
Are boys more familiar with ‘Declarative Fractions’ than girls?
(funny fact: ‘Declarative Fraction’ is a fake concept that is used in PISA to measure overconfidence)
(funny fact 2: plot familiarity with ‘Declarative Fractions’ across countries, results are very interesting)
library(ggplot2)
library(reshape2)
library(likert)
library(intsvy)
# read students data from PISA 2012
# directly from URL
con <- url("http://beta.icm.edu.pl/PISAcontest/data/student2012.rda")
load(con)
# variable ST62Q13 codes familiarity with 'Declarative Fraction'
tab <- pisa.table(variable="ST62Q13", by="ST04Q01", data=student2012)
ptab <- acast(tab, ST04Q01~ST62Q13, value.var="Percentage")
ddat <- data.frame(Item=rownames(ptab), ptab)
# plot it with the likert package
likert.bar.plot(likert(summary=ddat), center=2) + ggtitle("Declarative Fraction") + theme_bw() |
In which countries the fraction of kids that declare that they are happy at school is the highest?
# variable ST87Q07 codes 'Sense of Belonging - Feel Happy at School'
# pisa.table calculates weighted fractions and it's standard errors
tab <- pisa.table(variable="ST87Q07", by="CNT", data=student2012)
ptab <- acast(tab, CNT~ST87Q07, value.var="Percentage")
# need to add fake column with 0, otherwise likert.bar.plot will fail
ddat <- data.frame(Item=rownames(ptab), cbind(ptab[,4:3], 0, ptab[,2:1]))
ddat <- ddat[-grep(rownames(ddat),pattern="(", fixed=TRUE),]
# plot it with the likert package
likert.bar.plot(likert(summary=ddat), plot.percent.neutral=FALSE) + ggtitle("Sense of Belonging - Feel Happy at School") |
There is a lot of ‘kind of Likert’ scale questions in the PISA study, for sure there is a lot of nice stories as well.
R-bloggers.com offers daily e-mail updates about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job.
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.