Classifier for Times headlines

times_only.R

### Load libraries
library(RTextTools)

### Make sure .xlsx file has been converted to CSV properly
	media <- read.csv("media1960-2008_websiteversion_111007.csv",
		header=T,as.is=T)
	media$Date <- as.Date(media$Date,"%d/%m/%Y")
	media <- subset(media,Date > as.Date("1996-01-01"))
	media <- media[,c("Title","Subtitle","Major_Topic")]

media_matrix <- create_matrix(cbind(media["Title"],media["Subtitle"]), 
	language="english", removeNumbers=TRUE, 
	stemWords=TRUE, weighting=weightTfIdf)


corpus <- create_container(media_matrix,media$Major_Topic,
	trainSize=1:5700,testSize=5701:nrow(media),
	virgin=FALSE)

names(attributes(corpus)) #class matrix_container

models <- train_models(corpus, algorithms=c("SVM","MAXENT"))

results <- classify_models(corpus, models)

##########################################
# VIEW THE RESULTS BY CREATING ANALYTICS #
##########################################
analytics <- create_analytics(corpus, results)

head(analytics@algorithm_summary)
head(analytics@label_summary)
head(analytics@document_summary)
analytics@ensemble_summary

# WRITE OUT THE DATA TO A CSV --- look in your working directory
write.csv(analytics@algorithm_summary,"times_AlgorithmSummary.csv")
write.csv(analytics@label_summary,"times_LabelSummary.csv")
write.csv(analytics@document_summary,"times_DocumentSummary.csv")
write.csv(analytics@ensemble_summary,"times_EnsembleSummary.csv")