TY - JOUR AU - Tena Cucala, David J AU - Wałęga, Przemysław A AU - Cuenca Grau, Bernardo AU - Kostylev, Egor PY - 2021/05/18 Y2 - 2024/03/29 TI - Stratified Negation in Datalog with Metric Temporal Operators JF - Proceedings of the AAAI Conference on Artificial Intelligence JA - AAAI VL - 35 IS - 7 SE - AAAI Technical Track on Knowledge Representation and Reasoning DO - 10.1609/aaai.v35i7.16804 UR - https://ojs.aaai.org/index.php/AAAI/article/view/16804 SP - 6488-6495 AB - 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. ER -