TreeAnnotator: Versatile Visual Annotation of Hierarchical Text Relations

We introduce TREEANNOTATOR, a graphical tool for annotating tree-like structures, in particular structures that jointly map dependency relations and inclusion hierarchies, as used by Rhetorical Structure Theory (RST).TREEANNOTATOR is browser-based, embedded within the UIMA framework and provides two visualization modes.TREEANNOTATOR's interoperability exceeds similar tools, providing a wider range of formats, while annotation work can be completed more quickly due to a revised input method for RST dependency relations.TREEANNOTATOR offers a multiple window view, which allows users to inspect several annotations side by side.For storing and versioning annotations, the UIMA Database Interface (UIMA DI) was developed to save documents based on a pre-defined type system.These features not only connect TREEANNOTATOR annotations to modern technological and dialog theoretical work, but set it apart from related tools.The ease of use of TREEANNOTATOR and its newly designed user interface is evaluated in a user study consisting of annotating rhetorical relations with TREEANNOTATOR and the classic RSTTool.