Twitter Sentiment Analysis- results bias positive/negative
I am new user of RapidMiner. I am following some tutorial from rapidminer users in youtube to build a twitter sentiment analysis process. It was run well but the result was not really good. For example, when I used decision tree, it will give all positive sentiment (no negative or neutral). When I used SVM, the results will all negative. My trainning data was mixed positive and negative. Can anaybody advice. Thanks.