Dr. Ahmet Kara

I am a computer scientist who has a strong theoretical background and is also interested in contributing to the design of practically relevant systems based on well-understood theory. The main focus of my research is the design and analysis of efficient algorithms to solve difficult data processing tasks. 

In my postdoctoral research, I worked on the incremental maintenance of database and machine learning workloads. I contributed to the design of a system that uses reinforcement learning for query evaluation. I also investigated game theoretic notions to explain the contributions of input records to the results of queries and designed compressed representations of relational data. Before that, I investigated logics in formal system verification. Hence, my research covers a wide range of topics in computer science. 

• Incremental Maintenance of Complex Data Analytics 
• Database Management Techniques for Efficient Machine Learning over Relational Data
• Reinforcement Learning for Efficient Query Evaluation
• Explaining Query Results Using Game Theory
• Logics and Automata for Formal System Verification

• Since May 2020: Senior researcher (Oberassistent) in the DAST group, Department of Informatics, University of Zurich
• October 2016 - May 2020: Postdoctoral reasearcher in the Department of Computer Science, University of Oxford
• 2009 - 2015: Research Assistant and PhD Student at the Technical University of Dortmund

Journal Publications 

• Junxiong Wang, Immanuel Trummer, Ahmet Kara, Dan Olteanu: ADOPT: Adaptively Optimizing Attribute Orders for Worst-Case Optimal Join Algorithms via Reinforcement Learning. Proceedings of the VLDB Endowment 2023. DOI: https://doi.org/10.14778/3611479.3611489
• Junxiong Wang, Mitchell Gray, Immanuel Trummer, Ahmet Kara, Dan Olteanu: Demonstrating ADOPT: Adaptively Optimizing Attribute Orders for Worst-Case Optimal Joins via Reinforcement Learning. Proceedings of the VLDB Endowment 2023. DOI: https://doi.org/10.14778/3611540.3611629
• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Trade-offs in Static and Dynamic Evaluation of Hierarchical Queries. Logical Methods in Computer Science (LMCS) 2023. DOI: https://doi.org/10.48550/arXiv.1907.01988 
• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: F-IVM: Analytics over Relational Databases under Updates}. The VLDB Journal 2023. https://doi.org/10.1007/s00778-023-00817-w 
• Ahmet Kara, Hung Q. Ngo, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Maintaining Triangle Queries under Updates. ACM Transactions of Database Systems (TODS 2020). https://doi.org/10.1145/3396375

Conference Publications

• Ahmet Kara, Dan Olteanu, Dan Suciu: From Shapley Value to Model Counting and Back}. Accepted by the ACM Symposium on Principles of Database Systems (PODS) 2024. ArXiv: https://arxiv.org/abs/2306.14211
• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Conjunctive Queries with Free Access Patterns under Updates. International Conference on Database Theory (ICDT) 2023. DOI: https://doi.org/10.4230/LIPIcs.ICDT.2023.17
• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Evaluation Trade-Offs for Acyclic Conjunctive Queries. Conference for Computer Science Logic (CSL) 2023. DOI: https://doi.org/10.4230/LIPIcs.CSL.2023.29
• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Trade-offs in Statical and Dynamic Evaluation of Hierarchical Queries. ACM Symposium on Principles of Database Systems (PODS) 2020. DOI: https://doi.org/10.1145/3375395.3387646
• Milos Nikolic, Haozhe Zhang, Ahmet Kara, Dan Olteanu: F-IVM: Learning over Fast-Evolving Relational Data. International Conference on Management of Data (SIGMOD) 2020. Demo. DOI: https://doi.org/10.1145/3318464.3384702
• Ahmet Kara, Hung Q. Ngo, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Counting Triangles under Updates in Worst-Case Optimal Time. International Conference on Database Theory (ICDT) 2019. DOI: https://doi.org/10.4230/LIPIcs.ICDT.2019.4
• Ahmet Kara, Dan Olteanu: Covers of Query Results. International Conference on Database Theory (ICDT) 2018. DOI: https://doi.org/10.4230/LIPIcs.ICDT.2018.16
• Parosh Aziz Abdulla, Mohamed Faouzi Atig, Ahmet Kara, Othmane Rezine: Verification of Buffered Dynamic Register Automata. International Conference on Networked Systems (NETYS) 2015. DOI: https://doi.org/10.1007/978-3-319-26850-7\_2
• Parosh Aziz Abdulla, Mohamed Faouzi Atig, Ahmet Kara, Othmane Rezine: Verification of Dynamic Register Automata. Conference on Foundations of Software Technology and Theoretical Computer Science (FSTTCS) 2014. DOI: https://doi.org/10.4230/LIPIcs.FSTTCS.2014.653
• Benedikt Bollig,   Cyriac, Loïc Hélouët, Ahmet Kara, Thomas Schwentick: Dynamic Communicating Automata and Branching High-Level MSCs. Conference on Language and Automata Theory and Applications (LATA) 2013. DOI: https://doi.org/10.1007/978-3-642-37064-9\_17

• Ahmet Kara, Thomas Schwentick, Tony Tan: Feasible Automata for Two-Variable Logic with Successor on Data Words. Conference on Language and Automata Theory and Applications (LATA) 2012. DOI: https://doi.org/10.1007/978-3-642-28332-1\_30

• Ahmet Kara, Thomas Schwentick, Thomas Zeume:  Temporal Logics on Words with Multiple Data Values. Conference on Foundations of Software Technology and Theoretical Computer Science (FSTTCS) 2010. DOI: https://doi.org/10.4230/LIPIcs.FSTTCS.2010.481

• Ahmet Kara, Volker Weber, Martin Lange, Thomas Schwentick: On the Hybrid Extension of CTL and CTL+. International Symposium on Mathematical Foundations of Computer Science (MFCS) 2009.  DOI: https://doi.org/10.1007/978-3-642-03816-7\_37

Peer-Reviewed Workshop Publications

• Ahmet Kara, Hung Q. Ngo, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Counting Triangles under Updates. Alberto Mendelzon International Workshop on Foundations of Data Management (AMW) 2018. http://ceur-ws.org/Vol-2100/paper12.pdf

• Ahmet Kara, Thomas Schwentick: Expressiveness of Hybrid Temporal Logic on Data Words} \\
  Electronic Notes in Theoretical Computer Science (ENTCS) 2011. DOI: https://doi.org/10.1016/j.entcs.2011.10.010

Tutorial Papers at Conferences

• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Machine Learning Over Static and Dynamic Relational Data. ACM International Conference on Distributed and Event-based Systems (DEBS) 2021. DOI: https://doi.org/10.1145/3465480.3467843
• Iman Elghandour, Ahmet Kara, Dan Olteanu, Stijn Vansummeren:  Incremental Techniques for Large-Scale Dynamic Query Processing. ACM International Conference on Information and Knowledge Management (CIKM) 2018. DOI: https://doi.org/10.1145/3269206.3274271

PhD Thesis

• Ahmet Kara: Logics on data words: Expressivity, Satisfiability, Model checking. Technical University of Dortmund, Germany 2016.  http://hdl.handle.net/2003/35216

Tutorial Papers at Conferences

• Ahmet Kara, Milos Nikolic, Dan Olteanu, Haozhe Zhang: Machine Learning Over Static and Dynamic Relational Data. ACM International Conference on Distributed and Event-based Systems (DEBS) 2021. DOI: https://doi.org/10.1145/3465480.3467843
• Iman Elghandour, Ahmet Kara, Dan Olteanu, Stijn Vansummeren:  Incremental Techniques for Large-Scale Dynamic Query Processing. ACM International Conference on Information and Knowledge Management (CIKM) 2018. DOI: https://doi.org/10.1145/3269206.3274271