Analysis of Singapore's Education using three datasets

BigTable.R

library("ggplot2")
source("PupilsPerTeacherRatio.R") # load our data
source("ExpenditurePerStudent_Pupils.R") # load the data

data = matrix(c(cleanedData.pupils$Years, cleanedData.pupils$ExpednInSD, 
                cleanedData.ratio$PupilsPerTeacher), ncol=3)
df = data.frame(data)
colnames(df) <- c("Year", "MoneySpend", "Ratio")

#TODO ggplot
pl = plot(x=df$Year, y=log(df$MoneySpend), ylim=c(2,10), main ="Red points are the ratio, which should be declining. 
          Whereas dark points are money spend on each student.")
points(x=df$Year, y=log(df$Ratio), col=2)

ClassSize.R

# let's load some data from Excel :_
suppressMessages(library("XLConnect"))
library("plyr")

#  Number of Classes and Class Size by Level 
if(!file.exists("NumberOfClassesSizeLevel.xlsx")) {
  #download.file("http://data.gov.sg/Metadata/SGMatadata.aspx?id=0304010000000005778F", 
  #              "NumberOfClassesSizeLevel.xlsx.xlsx")
} 

loadedXLSofData.class = loadWorkbook("NumberOfClassesSizeLevel.xlsx")
rawTable.class = readWorksheet(loadedXLSofData.class, 1)

#Begin with just 2 columns
#select only primary "all" and secondary "all"
rawTable.class.twoCol <- rawTable.class[c("Year","Description", 
                                          "CLASSES.AND.CLASS.SIZE.BY.LEVEL...PUBLIC.SCHOOLS", 
                                       "CLASSES.AND.CLASS.SIZE.BY.LEVEL...PUBLIC.SCHOOLS.9")]

#rename column names to make it more clear for next steps
colnames(rawTable.class.twoCol) <- c("Year", "Description", 
                                     "AllNumbersForPrimarySchools", "AllNumbersForSecondarySchools")

#select row by its description and devide them into two tables
numberOfClases = subset(rawTable.class.twoCol,rawTable.class.twoCol$Description=="NO OF CLASSES")
avarageClassSize = subset(rawTable.class.twoCol,rawTable.class.twoCol$Description=="AVE CLASS SIZE")

#great; both are chars. We need to convert them
class(numberOfClases$AllNumbersForPrimarySchools)
class(numberOfClases$Year)
class(avarageClassSize$AllNumbersForSecondarySchools) 

cleanedData.numberOfClases = suppressWarnings(data.frame(llply(numberOfClases, as.numeric)))
# because we apply as.numeric to chars we introduce NA (and warnings [sic!])
cleanedData.numberOfClases$Description <- NULL

cleanedData.avarageClassSize = suppressWarnings(data.frame(llply(avarageClassSize, as.numeric)))
cleanedData.avarageClassSize$Description <- NULL

ExpenditurePerStudent_Pupils.R

# let's load some data from Excel :_
suppressMessages(library("XLConnect"))
library("plyr")

if(!file.exists("ExpenditurePerStudent_PS.xls")) {
  download.file("http://data.gov.sg/Agency_Data/MOE/0303010000000005772Z.xls", 
                "ExpenditurePerStudent_PS.xls")
} 

loadedXLSofData.pupils = loadWorkbook("ExpenditurePerStudent_PS.xls")
rawTable.pupils = readWorksheet(loadedXLSofData.pupils, 1)

rawData.pupils = rename(rawTable.pupils[3:30,0:2], c("X2.0" = "Years", "SGDATA" = "ExpednInSD"))
# summary(rawData) # DF which is a list

rawData.pupils$Years <- with(rawData.pupils, 
                             replace(rawData.pupils$Years, 
                                     rawData.pupils$Years == "2013*", "2013"))

# NUMERIC all
cleanedData.pupils = data.frame(llply(rawData.pupils, as.numeric))
cleanedData.pupils = cleanedData.pupils[cleanedData.pupils$Years<=2012,]

summary(lm(cleanedData.pupils$ExpednInSD ~ cleanedData.pupils$Years))
cor(cleanedData.pupils$Years, cleanedData.pupils$ExpednInSD)

PupilsPerTeacherRatio.R

library("XLConnect")
library("plyr")

loadedXLSofData.ratio = loadWorkbook("PupilsPerTeacherPrimarySchools.xlsx")
rawTable.ratio = readWorksheet(loadedXLSofData.ratio, 1)

rawData.ratio = rename(rawTable.ratio[2:nrow(rawTable.ratio),], c("X0301050000000005757K" = "Years",
                                               "Col2" = "PupilsPerTeacher"))

cleanedData.ratio = data.frame(llply(rawData.ratio, as.numeric))
cleanedData.ratio = cleanedData.ratio[cleanedData.ratio$Years>=1986,]

summary(  lm(cleanedData.ratio$PupilsPerTeacher ~ cleanedData.ratio$Years))

(as of 2017, cannot be used anymore)
https://ref.data.gov.sg/Metadata/SGMatadata.aspx?id=0304010000000005778F&mid=135758&t=TEXTUAL
https://ref.data.gov.sg/Metadata/SGMatadata.aspx?id=0301050000000005757K&mid=105030&t=TEXTUAL
https://ref.data.gov.sg/Metadata/SGMatadata.aspx?id=0303010000000005772Z&mid=104977&t=TEXTUAL