|Date: 12th April 2011 (Tuesday) |
| Time: 14:00 - 15:00 |
| Venue: MB504 |
Recent years have seen a tremendous increase of structured data on the Web with Linked Open Data project encouraging publication of even more. This massive amount of data requires effective exploitation which is now a big challenge largely because of the complexity and syntactic unfamiliarity of the underlying triple models and the query languages built on top of them. Natural Language Interfaces are increasingly relevant for information systems fronting rich structured data stores such as RDF and OWL repositories, largely because of the conception of them being intuitive for human. Many NLIs to ontologies have been developed, however little work has been done in testing the usability of these systems and the usability enhancement methods which can improve their performance. We assess the effect of these methods through the two user-centric studies of the two systems: QuestIO and FREyA. The first study assesses the usability of QuestIO, which is fully automatic, in comparison to the traditional ways of search. The second one assesses the usability of FREyA, which involves the user into loop, with special emphasis on feedback. Our results highlight the expressiveness of the language supported by QuestIO and FREyA, and also the importance of feedback which is shown to improve the overall usability and user experience. In addition, combination of feedback and clarification dialogs in FREyA is shown to outperform the state of the art systems.