@article{Tena Cucala_Wałęga_Cuenca Grau_Kostylev_2021, title={Stratified Negation in Datalog with Metric Temporal Operators}, volume={35}, url={https://ojs.aaai.org/index.php/AAAI/article/view/16804}, DOI={10.1609/aaai.v35i7.16804}, abstractNote={We extend DatalogMTL—Datalog with operators from metric temporal logic—by adding stratified negation as failure. The new language provides additional expressive power for representing and reasoning about temporal data and knowledge in a wide range of applications. We consider models over the rational timeline, study their properties, and establish the computational complexity of reasoning. We show that, as in negation-free DatalogMTL, fact entailment in our language is PSPACE-complete in data and EXPSPACE-complete in combined complexity. Thus, the extension with stratified negation does not lead to higher complexity.}, number={7}, journal={Proceedings of the AAAI Conference on Artificial Intelligence}, author={Tena Cucala, David J and Wałęga, Przemysław A and Cuenca Grau, Bernardo and Kostylev, Egor}, year={2021}, month={May}, pages={6488-6495} }