Which word stemmer should I use in nltk? <p>My goal is to analyze some corpus (twitter for the now) for emotional content. Just today I realized it would make a bit of sense to search for word stems as opposed to having an exhaustive list of emotional word stems. And so I've been exploring nltk.stem only to realize that there are 4 different stemmers. I'd like to ask the stackoverflow linguists whether LancasterStemmer, PorterStemmer, RegexpStemmer, RSLPStemmer, or WordNetStemmer is best preferably with some justification.</p>