Abstract
The present paper deals with morphographemic alternations in Czech derivation with regard to the build-up of a large-coverage lexical resource specialized in derivational morphology of contemporary Czech (DeriNet database). After a summary of available descriptions in the Czech linguistic literature and Natural Language Processing, an extensive list of alternations is provided in the first part of the paper with a focus on their manifestation in writing.
Due to the significant frequency and limited predictability of alternations in Czech derivation, several bottom-up methods were used in order to adequately model the alternations in DeriNet. Suffix-substitution rules proved to be efficient for alternations in the final position of the stem, whereas a specialized approach of extracting alternations from inflectional paradigms was used for modelling alternations within the roots.
Alternations connected with derivation of verbs were handled as a separate task. DeriNet data are expected to be helpful in d