Detecting syntactic errors in dependency treebanks for morphosyntactically rich languages

Abstract. The paper introduces a new method for detecting and correcting errors in large dependency treebanks with rich morphosyntactic annotation. The technique uses error correction rules automatically extracted from the treebank. The procedure of rule extraction is based on a comparison of similar -but not identical -subgraphs of dependency structures. The outcome of applying the method to a 3-million-sentence dependency treebank of Polish is presented and evaluated. The method achieves satisfactory precision in the task of automatic error correction and relatively high precision in the task of error detection