By Alex Danvers
What words can classify a movie review as positive? What words classify it as negative?
In the symposium Big Data: Vast Opportunities for Psychological Insight from Mining Enormous Datasets at the SPSP Annual Convention, Harvard economist Sendil Mullainathan threw up some obvious candidates, like “dazzling” or “gripping”—words that researchers brainstormed would do a good job. Using these “theory-grounded” words, a team of computer scientists was able to classify reviews with 60% accuracy—not much of an improvement over 50/50 guessing.