Identify opinion orientation on feature
For each feature, we identify the sentiment or opinion orientation expressed by a reviewer.
We work based on sentences, but also consider,
A sentence can contain multiple features.
Different features may have different opinions.
E.g., The battery life and picture quality are great (+), but the view founder is small (-).
Almost all approaches make use of opinion words and phrases. But notice again:
Some opinion words have context independent orientations, e.g., “great”.
Some other opinion words have context dependent orientations, e.g., “small”
Many ways to use them.