Congratulations for sticking with us until the end! Together we have learned how Naive Bayes work and why they are not that naive at all. For training sets where we don't have enough data to learn all the niches in the class probability space, Naive Bayes do a great job of generalizing. We learned how to apply them to tweets and that cleaning the rough tweets' text helps a lot. Finally, we realized that a bit of "cheating" (only after we have done our fair share of work) is OK, especially, when it gives another improvement of the classifier's performance, as we have experienced with the use of SentiWordNet.