1. A method of categorizing messages, comprising: receiving, by a first server from a second server maintaining a plurality of social media messages, a message, the first server configured to categorize the message under a first category or a second category; removing, by the first server, from the message, one or more words that match a predetermined set of stop words; replacing, by the first server, one or more character strings included in the message that are associated with stem words with the corresponding stem word; determining a frequency of each of the words included in the modified message; determining, using a probabilistic engine executing on the first server, a relevancy score of the modified message indicating a level of relevance between the message and the first category based on the determined frequency of each of the words, the probabilistic engine using training data including a first list of messages including a predetermined number of messages previously categorized under the first category and a second list of messages previously categorized under the second category, the second list of messages including the same predetermined number of messages as the first list of messages, the messages in the first list of messages or the messages in the second list of messages including one or more of the stem words; and responsive to determining that the relevancy score satisfies a threshold, categorizing the message under the first category.