Discontinuous Data-Oriented Parsing through Mild Context-Sensitivity Andreas van Cranenburgh Abstract: It has long been argued that incorporating a notion of discontinuity in phrase-structure is desirable, given phenomena such as topicalization and extraposition, and particular features of languages such as cross-serial dependencies in Dutch and the German Mittelfeld. Up until recently this was mainly a theoretical topic, but advances in parsing technology have made treebank parsing with discontinuous constituents possible, with favorable results. We improve on this by applying Data-Oriented Parsing (DOP) to a mildly context-sensitive grammar formalism which allows for discontinuous trees. Decisions during parsing are conditioned on all possible fragments, resulting in improved performance. Despite the fact that both DOP and discontinuity present formidable challenges in terms of computational complexity, the model is reasonably efficient. Our results emulate and surpass the state of the art in discontinuous parsing.