Stemming with R Text Analysis

Question

I am doing a lot of analysis with the TM package. One of my biggest problems are related to stemming and stemming-like transformations.

Let's say I have several accounting related terms (I am aware of the spelling issues).
After stemming we have:

accounts   -> account  
account    -> account  
accounting -> account  
acounting  -> acount  
acount     -> acount  
acounts    -> acount  
accounnt   -> accounnt  

Result: 3 Terms (account, acount, account) where I would have liked 1 (account) as all these relate to the same term.

1) To correct spelling is a possibility, but I have never attempted that in R. Is that even possible?

2) The other option is to make a reference list i.e. account = (accounts, account, accounting, acounting, acount, acounts, accounnt) and then replace all occurrences with the master term. How would I do this in R?

Once again, any help/suggestions would be greatly appreciated.

Answer 1

This question inspired me to attempt to write a spell check for the qdap package. There's an interactive version that may be useful here. It's available in qdap >= version 2.1.1. That means you'll need the dev version at the moment.. here are the steps to install:

library(devtools)
install_github("qdapDictionaries", "trinker")
install_github("qdap", "trinker")
library(tm); library(qdap)

## Recreate a Corpus like you describe.

terms <- c("accounts", "account", "accounting", "acounting", "acount", "acounts", "accounnt")

fake_text <- unlist(lapply(terms, function(x) {
    paste(sample(c(x, sample(DICTIONARY[[1]], sample(1:5, 1)))), collapse=" ")
}))

fake_text

inspect(myCorp <- Corpus(VectorSource(fake_text)))

## The interactive spell checker (check_spelling_interactive)

m <- check_spelling_interactive(as.data.frame(myCorp)[[2]])
preprocessed(m)
inspect(myCorp <- tm_map(myCorp, correct(m)))

The correct function merely grabs a closure function from the output of check_spelling_interactive and allows you to then apply the "correcting" to any new text string(s).