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: On #WADR, It's better for President Barack Obama to be optimistic than pessimistic (VIDEO) http://bloom.bg/1yqCifV  Responser: Halpern are you a liberal now???Immigration is TERRIBLE and you think it is great. MOST Americans HATE it.
