x <- as.data.frame(read.table(file='http://www.wessa.net/download/statdb.csv',sep=',',header=T))
postscript(file="/var/www/html/rcomp/tmp/1nv9k1213478238.ps",horizontal=F,pagecentre=F,paper="special",width=8.3333333333333,height=5.5555555555556) 
boxplot(x[x$Pop==0,'TX18'] ~ cut(x[x$Pop==0,'nnzfg'], c(0,100,450)), notch=T, main='# Submitted Verbal Feedback Messages', xlab='# Messages', ylab='Exam Scores (Bachelor)')
abline(7,0,col = 'lightgray', lty=3)
dev.off()
postscript(file="/var/www/html/rcomp/tmp/2c4dv1213478238.ps",horizontal=F,pagecentre=F,paper="special",width=8.3333333333333,height=5.5555555555556) 
boxplot(x[x$Pop==0,'TX18'] ~ cut(x[x$Pop==0,'nnzfr'], c(0,100,450)), notch=T, main='# Received Verbal Feedback Messages', xlab='# Messages', ylab='Exam Scores (Bachelor)')
abline(7,0,col = 'lightgray', lty=3)
dev.off()
postscript(file="/var/www/html/rcomp/tmp/32tbb1213478238.ps",horizontal=F,pagecentre=F,paper="special",width=8.3333333333333,height=5.5555555555556) 
boxplot(x[x$Pop==1,'TX18'] ~ cut(x[x$Pop==1,'nnzfg'], c(0,150,450)), notch=T, main='# Submitted Verbal Feedback Messages', xlab='# Messages', ylab='Exam Scores (Switching)')
abline(7,0,col = 'lightgray', lty=3)
dev.off()
postscript(file="/var/www/html/rcomp/tmp/40bb41213478238.ps",horizontal=F,pagecentre=F,paper="special",width=8.3333333333333,height=5.5555555555556) 
boxplot(x[x$Pop==1,'TX18'] ~ cut(x[x$Pop==1,'nnzfr'], c(0,170,450)), notch=T, main='# Received Verbal Feedback Messages', xlab='# Messages', ylab='Exam Scores (Switching)')
abline(7,0,col = 'lightgray', lty=3)
dev.off()

#Note: the /var/www/html/rcomp/createtable file can be downloaded at http://www.wessa.net/cretab
load(file="/var/www/html/rcomp/createtable")

a<-table.start()
a<-table.row.start(a)
a<-table.element(a,'Reproducible Computations - Descriptive Statistics',2,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Number of Bachelor students',header=TRUE)
a<-table.element(a,length(x[x$Pop==0,'TX18']))
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Number of Switching students',header=TRUE)
a<-table.element(a,length(x[x$Pop==1,'TX18']))
a<-table.row.end(a)
numws <- length(x[!is.na(x$WS1),'WS1']) + length(x[!is.na(x$WS2),'WS2']) + length(x[!is.na(x$WS3),'WS3']) + length(x[!is.na(x$WS4),'WS4']) + length(x[!is.na(x$WS5),'WS5']) + length(x[!is.na(x$WS6),'WS6']) + length(x[!is.na(x$WS7),'WS7']) + length(x[!is.na(x$WS8),'WS8']) + length(x[!is.na(x$WS9),'WS9']) + length(x[!is.na(x$WS10),'WS10']) + length(x[!is.na(x$WS11),'WS11']) + length(x[!is.na(x$WS12),'WS12'])
a<-table.row.start(a)
a<-table.element(a,'Number of submitted workshops',header=TRUE)
a<-table.element(a,numws)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Number of feedback grades',header=TRUE)
a<-table.element(a,sum(x[,'nfr']))
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Number of verbal feedback communications',header=TRUE)
a<-table.element(a,sum(x[,'nnzfr']))
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Average number of grades per workshop',header=TRUE)
a<-table.element(a,round(sum(x[,'nfr'])/numws,1))
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Average number of verbal feedback messages per workshop',header=TRUE)
a<-table.element(a,round(sum(x[,'nnzfr'])/numws,1))
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file="/var/www/html/rcomp/tmp/5czho1213478238.tab") 
a<-table.start()
a<-table.row.start(a)
a<-table.element(a,'Reproducible Computations - Two-dimensional Contingency Table - by population',6,TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Bachelor',header=TRUE)
a<-table.element(a,'# Submitted Verbal Feedback Messages',2,header=TRUE)
a<-table.element(a,' ',header=TRUE)
a<-table.element(a,'# Received Verbal Feedback Messages',2,header=TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Exam Score',header=TRUE)
a<-table.element(a,'(0,100]',header=TRUE)
a<-table.element(a,'(100,450]',header=TRUE)
a<-table.element(a,' ',header=TRUE)
a<-table.element(a,'(0,100]',header=TRUE)
a<-table.element(a,'(100,450]',header=TRUE)
a<-table.row.end(a)
(mytg <- table(cut(x[x$Pop==0,'TX18'],c(-3,4,7,18)),cut(x[x$Pop==0,'nnzfg'],c(0,100,450))))
(mychsqtg <- chisq.test(mytg))
(mytr <- table(cut(x[x$Pop==0,'TX18'],c(-3,4,7,18)),cut(x[x$Pop==0,'nnzfr'],c(0,100,450))))
(mychsqtr <- chisq.test(mytr))
a<-table.row.start(a)
a<-table.element(a,'(-3,4]',header=TRUE)
a<-table.element(a,mytg[1,1])
a<-table.element(a,mytg[1,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[1,1])
a<-table.element(a,mytr[1,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'(4,7]',header=TRUE)
a<-table.element(a,mytg[2,1])
a<-table.element(a,mytg[2,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[2,1])
a<-table.element(a,mytr[2,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'(7,18]',header=TRUE)
a<-table.element(a,mytg[3,1])
a<-table.element(a,mytg[3,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[3,1])
a<-table.element(a,mytr[3,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'X-squared',header=TRUE)
a<-table.element(a,mychsqtg$statistic,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$statistic,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'degrees of freedom',header=TRUE)
a<-table.element(a,mychsqtg$parameter,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$parameter,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'p value',header=TRUE)
a<-table.element(a,mychsqtg$p.value,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$p.value,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,' ',6)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Switching',header=TRUE)
a<-table.element(a,'# Submitted Verbal Feedback Messages',2,header=TRUE)
a<-table.element(a,' ',header=TRUE)
a<-table.element(a,'# Received Verbal Feedback Messages',2,header=TRUE)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'Exam Score',header=TRUE)
a<-table.element(a,'(0,150]',header=TRUE)
a<-table.element(a,'(150,450]',header=TRUE)
a<-table.element(a,' ',header=TRUE)
a<-table.element(a,'(0,170]',header=TRUE)
a<-table.element(a,'(170,450]',header=TRUE)
a<-table.row.end(a)
(mytg <- table(cut(x[x$Pop==1,'TX18'],c(-3,4,7,18)),cut(x[x$Pop==1,'nnzfg'],c(0,150,450))))
(mychsqtg <- chisq.test(mytg))
(mytr <- table(cut(x[x$Pop==1,'TX18'],c(-3,4,7,18)),cut(x[x$Pop==1,'nnzfr'],c(0,170,450))))
(mychsqtr <- chisq.test(mytr))
a<-table.row.start(a)
a<-table.element(a,'(-3,4]',header=TRUE)
a<-table.element(a,mytg[1,1])
a<-table.element(a,mytg[1,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[1,1])
a<-table.element(a,mytr[1,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'(4,7]',header=TRUE)
a<-table.element(a,mytg[2,1])
a<-table.element(a,mytg[2,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[2,1])
a<-table.element(a,mytr[2,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'(7,18]',header=TRUE)
a<-table.element(a,mytg[3,1])
a<-table.element(a,mytg[3,2])
a<-table.element(a,' ')
a<-table.element(a,mytr[3,1])
a<-table.element(a,mytr[3,2])
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'X-squared',header=TRUE)
a<-table.element(a,mychsqtg$statistic,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$statistic,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'degrees of freedom',header=TRUE)
a<-table.element(a,mychsqtg$parameter,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$parameter,2)
a<-table.row.end(a)
a<-table.row.start(a)
a<-table.element(a,'p value',header=TRUE)
a<-table.element(a,mychsqtg$p.value,2)
a<-table.element(a,' ')
a<-table.element(a,mychsqtr$p.value,2)
a<-table.row.end(a)
a<-table.end(a)
table.save(a,file="/var/www/html/rcomp/tmp/621u21213478238.tab") 

system("convert tmp/1nv9k1213478238.ps tmp/1nv9k1213478238.png")
system("convert tmp/2c4dv1213478238.ps tmp/2c4dv1213478238.png")
system("convert tmp/32tbb1213478238.ps tmp/32tbb1213478238.png")
system("convert tmp/40bb41213478238.ps tmp/40bb41213478238.png")