Fostering User Involvement in Ontology Alignment and Alignment Evaluation

The abundance of data at our disposal empowers data-driven applications and decisionmaking. The knowledge captured in the data, however, has not been utilized to fullpotential, as it is only accessible to human interpretation and data are distributed inheterogeneous repositories. Ontologies are a key technology unlocking the knowledge in the data by providingmeans to model the world around us and infer knowledge implicitly captured in the data.As data are hosted by independent organizations we often need to use several ontologiesand discover the relationships between them in order to support data and knowledgetransfer. Broadly speaking, while ontologies provide formal representations and thus thebasis, ontology alignment supplies integration techniques and thus the means to turn thedata kept in distributed, heterogeneous repositories into valuable knowledge. While many automatic approaches for creating alignments have already been devel-oped, user input is still required for obtaining the highest-quality alignments. This thesisfocuses on supporting users during the cognitively intensive alignment process and makesseveral contributions. We have identified frontand back-end system features that foster user involvementduring the alignment process and have investigated their support in existing systems byuser interface evaluations and literature studies. We have further narrowed down ourinvestigation to features in connection to the, arguably, most cognitively demanding taskfrom the users’ perspective—manual validation—and have also considered the level of userexpertise by assessing the impact of user errors on alignments’ quality. As developing andaligning ontologies is an error-prone task, we have focused on the benefits of the integrationof ontology alignment and debugging. We have enabled interactive comparative exploration and evaluation of multiple align-ments at different levels of detail by developing a dedicated visual environment—AlignmentCubes—which allows for alignments’ evaluation even in the absence of reference alignments. Inspired by the latest technological advances we have investigated and identified threepromising directions for the application of large, high-resolution displays in the field:improving the navigation in the ontologies and their alignments, supporting reasoning andcollaboration between users. The work has been supported by the Swedish Research Council (2010-4759),the Swedish Graduate School in Computer Science (CUGS), the Swedish e-ScienceResearch Centre (SeRC) and the EU FP7 project VALCRI (FP7-IP-608142).