Definition: Given a 'poster' sentence and a corresponding 'response' (often, from Facebook or Reddit)classify the sentiment of the given response into four categories: 1) Positive, 2) Negative, 3) Neutral, and 4) Mixed if it contains both positive and negative.
Input: Poster: Ed will be a guest on WBUR 90.9 FM's Radio Boston this afternoon beginning at 3PM. Listen live in 10 minutes!  Responser: http://www.arktimes.com/ArkansasBlog/archives/2013/04/05/more-oil-spill-questions
