Each noun k is assigned to the topic with the higher PMI score.
if P M I(topic 1 ,k) > P M I(topic 2 ,k) ⇒k= topic 1 and if 4 http://cwl-projects.cogsci.rpi.edu/msr/ P M I(topic 2 ,k) > P M I(topic 1 ,k) ⇒k= topic 2 Next, the polarity-target pairs are found for the post, as before, and Equations 10 and 11 are used to assign a side to the post as in the OpTopic system, except that here, related nouns are also counted as instances of their associated topics.