Kjetil Nørvåg

About

Kjetil Nørvåg is a professor at the Department of Computer and Information Science at NTNU. He is affiliated with the Data and artificial intelligence group, where his main research interests include distributed and parallel database systems, query processing, information retrieval, and Big Data in general.

He has been involved in teaching on a wide range of topics, including Data mining, Big Data architecture, Advanced databases, Information retrieval, Distributed systems, Data modelling and database systems, Operating systems, Algorithms and data structures, Computer architecture, and Computer systems.

Nørvåg has been involved in a number of projects during recent years, including:

Norwegian Center for Research-based AI Innovation (NorwAI), 26M Euro (Centre for Research-based Innovation, funding from NTNU, Norwegian Research Council, and industry partners), 2020-2028.
Big Data & Machine Learning, 0.5M Euro per year (funded by DNB), 2018-2023.
Trondheim Analytica (NTNU Digital Transformation program), 2018-2022.
ExiBiDa: Exploring new dimensions in Big Data, funding one PhD student and one postdoc, approx. 1M Euro (Norwegian Research Council), 2015-2019.
CoupledDB: High-Performance Indexing for Emerging GPU-Coupled Databases, 208K Euro (EU H2020-MSCA), 2017-2019.
MUSED: Multi-Source Event Detection, 7M NOK (NTNU funded), 2017-2021.
CloudIX: Cloud-based Indexing and Query Processing, 212K Euro (EU FP7 with partial funding from the Norwegian Research Council), 2011-2013.
COMIDOR: Cooperative Mining of Independent Document Repositories, funding two PhD students and two postdocs, approx. 1.1M Euro (Norwegian Research Council), 2008-2013.
DASCOSA: Database Support for Computational Science Applications,, funding one PhD student and one postdoc, approx. 400K Euro (Norwegian Research Council), 2007-2012.
LongRec: Records Management over Decades (Consortium led by DNV), approx. 2.1M Euro (partially funded by the Norwegian Research Council), 2007-2011.

Nørvåg has published close to 200 publications. For a complete list, including links to preprints of the papers, please check out his CV

Publications

2025

Cerquitelli, Tania; Vargas-Solar, Genoveva; Chiusano, Silvia; Apiletti, Daniele; Belhajjame, Khalid; Berta, Matteo. (2025) Data Analytics solutions for Real-LIfe APplications (DARLI-AP). CEUR Workshop Proceedings
Editorial
Nanni, Mirco; Pelekis, Nikos; Tampakis, Panagiotis; Zeitouni, Karine; Sakr, Mahmoud; Renso, Chiara. (2025) Big Mobility Data Analytics (BMDA). CEUR Workshop Proceedings
Editorial
Abedi Firouzjaei, Hassan; Nørvåg, Kjetil; Gupta, Dhruv. (2025) Unveiling Novel Patterns of User Interactions in Online Communities. Doctoral theses at NTNU (223)
Doctoral dissertation

2024

Shadrooh, Shiva; Nørvåg, Kjetil. (2024) SMoTeF: Smurf money laundering detection using temporal order and flow analysis. Applied intelligence (Boston)
Academic article
Shadrooh, Shiva; Nørvåg, Kjetil. (2024) Datis: data augmentation for trust intensity prediction in incomplete signed networks. Social Network Analysis and Mining
Academic article

2023

Theodoropoulos, George S.; Nørvåg, Kjetil; Doulkeridis, Christos. (2023) Efficient Semantic Similarity Search over Spatio-textual Data. OpenProceedings
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Rocha-Junior, Joao B.; Nørvåg, Kjetil. (2023) Decisive skyline queries for truly balancing multiple criteria. Data & Knowledge Engineering
Academic article

2021

Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil; Dam, Thu-Lan. (2021) Density Guarantee on Finding Multiple Subgraphs and Subtensors. ACM Transactions on Knowledge Discovery from Data
Academic article
Dam, Thu-Lan; Chester, Sean; Nørvåg, Kjetil; Duong, Quang-Huy. (2021) Efficient top-k recently-frequent term querying over spatio-temporal textual streams. Information Systems
Academic article

2020

Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2020) Multiple Dense Subtensor Estimation with High Density Guarantee. IEEE Press
Academic chapter/article/Conference paper
Maropaki, Stella; Chester, Sean; Doulkeridis, Christos; Nørvåg, Kjetil. (2020) Diversifying Top-k Point-of-Interest Queries via Collective Social Reach. ACM Publications
Academic chapter/article/Conference paper

2019

Djenouri, Youcef; Lin, Chun Wei; Nørvåg, Kjetil; Ramampiaro, Heri. (2019) Highly Efficient Pattern Mining Based on Transaction Decomposition. IEEE Press
Academic chapter/article/Conference paper
Trattner, Christoph; Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2019) Investigating and predicting online food recipe upload behavior. Information Processing & Management
Academic article
Özdikis, Özer; Ramampiaro, Heri; Nørvåg, Kjetil. (2019) Locality-adapted kernel densities of term co-occurrences for location prediction of tweets. Information Processing & Management
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2019) Sketching Streaming Histogram Elements using Multiple Weighted Factors. ACM Publications
Academic chapter/article/Conference paper

2018

Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2018) On Validation and Predictability of Digital Badges’ Influence on Individual Users. Proceedings of the AAAI Conference on Artificial Intelligence
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Applying temporal dependence to detect changes in streaming data. Applied intelligence (Boston)
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil; Fournier-Viger, Philippe; Dam, Thu-Lan. (2018) High utility drift detection in quantitative data streams. Knowledge-Based Systems
Academic article
Özdikis, Özer; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Locality-adapted Kernel Densities for Tweet Localization. ACM Publications
Academic chapter/article/Conference paper

2017

Benetka, Jan; Balog, Krisztian; Nørvåg, Kjetil. (2017) Anticipating Information Needs Based on Check-in Activity. ACM Publications
Academic chapter/article/Conference paper
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2017) Exploratory product search using top-k join queries. Information Systems
Academic article

2016

Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2016) Online Food Recipe Title Semantics: Combining Nutrient Facts and Topics. ACM Publications
Academic chapter/article/Conference paper
Saouk, Mei; Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil. (2016) Efficient processing of top-k joins in MapReduce. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper
Chester, Sean; Gkorgkas, Orestis; Nørvåg, Kjetil. (2016) Top-k Dominating Queries, in Parallel, in Memory. OpenProceedings
Academic chapter/article/Conference paper

2015

Larrain, Santiago; Trattner, Christoph; Parra, Denis; Graells-Garrido, Eduardo; Nørvåg, Kjetil. (2015) Good Times Bad Times: A Study on Recency Effects in Collaborative Filtering for Social Tagging. ACM Publications
Other
Kanhabua, Nattiya; Blanco, Roi; Nørvåg, Kjetil. (2015) Temporal Information Retrieval. Now Publishers Inc. Now Publishers Inc.
Academic monograph
Kusmierczyk, Tomasz; Trattner, Christoph; Nørvåg, Kjetil. (2015) Temporality in Online Food Recipe Consumption and Production. ACM Publications
Other
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2015) Finding the Most Diverse Products using Preference Queries. OpenProceedings
Academic chapter/article/Conference paper

2014

Doulkeridis, Christos; Nørvåg, Kjetil. (2014) A survey of large-scale analytical query processing in MapReduce. The VLDB journal
Academic literature review
Kotsakos, Dimitrios; Lappas, Theodoros; Kotzias, Dimitrios; Gunopulos, Dimitrios; Kanhabua, Nattiya; Nørvåg, Kjetil. (2014) A burstiness-aware approach for document dating. ACM Publications
Academic chapter/article/Conference paper

2013

Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Kotidis, Yannis. (2013) Branch-and-bound algorithm for reverse top-k queries. ACM Publications
Academic chapter/article/Conference paper
Ciglan, Marek; Laclavik, Michal; Nørvåg, Kjetil. (2013) On community detection in real-world networks and the importance of degree assortativity. ACM Publications
Academic chapter/article/Conference paper

2012

Rocha-Junior, Joao B.; Nørvåg, Kjetil. (2012) Top-k spatial keyword queries on road networks. ACM Publications
Academic chapter/article/Conference paper
Ciglan, Marek; Nørvåg, Kjetil; Hluchy, Ladislav. (2012) The SemSets model for ad-hoc semantic list search. ACM Publications
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2012) Distributed top-k query processing by exploiting skyline summaries. Distributed and parallel databases
Academic article

2011

Rocha-Junior, Joao B.; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2011) Efficient Execution Plans for Distributed Skyline Query Processing. ACM Publications
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Kotidis, Yannis; Nørvåg, Kjetil. (2011) Monochromatic and Bichromatic Reverse Top-k Queries. IEEE Transactions on Knowledge and Data Engineering
Academic article

2010

Zhang, Xiangliang; Wang, Wei; Nørvåg, Kjetil; Sebag, Michele. (2010) K-AP: Generating Specified K Clusters by Efficient Affinity Propagation. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper
Hauglid, Jon Olav; Ryeng, Norvald Hegelstad; Nørvåg, Kjetil. (2010) DYFRAM: dynamic fragmentation and replica management in distributed database systems. Distributed and parallel databases
Academic article
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Kotidis, Yannis. (2010) Identifying the Most Influential Data Objects with Reverse Top-k Queries. Proceedings of the VLDB Endowment
Academic article
Ciglan, Marek; Nørvåg, Kjetil. (2010) WikiPop: personalized event detection system based on Wikipedia page view statistics. ACM Publications
Academic chapter/article/Conference paper
Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2010) On the selectivity of multidimensional routing indices. ACM Publications
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Kotidis, Yannis; Nørvåg, Kjetil. (2010) Reverse Top-k Queries. IEEE Press
Academic chapter/article/Conference paper
Rocha-Junior, Joao B.; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2010) Efficient Processing of Top-k Spatial Preference Queries. Proceedings of the VLDB Endowment
Academic article

2009

Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2009) Multidimensional Routing Indices for Efficient Distributed Query Processing. Association for Computing Machinery (ACM)
Academic chapter/article/Conference paper
Hauglid, Jon Olav; Nørvåg, Kjetil; Ryeng, Norvald Hegelstad. (2009) Efficient and Robust Database Support for Data-Intensive Applications in Dynamic Environments. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper

2008

Vlachou, Akrivi; Doulkeiridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) On efficient top-k query processing in highly distributed environments. ACM Publications
Academic chapter/article/Conference paper
Hauglid, Jon Olav; Nørvåg, Kjetil. (2008) PROQID: Partial Restarts of Queries in Distributed Databases. Association for Computing Machinery (ACM)
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) Skyline-based Peer-to-Peer Top-k Query Processing. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper

2007

Doulkeridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2007) DESENT: decentralized and distributed semantic overlay generation in P2P networks. IEEE Journal on Selected Areas in Communications
Academic article

Journal publications

Cerquitelli, Tania; Vargas-Solar, Genoveva; Chiusano, Silvia; Apiletti, Daniele; Belhajjame, Khalid; Berta, Matteo. (2025) Data Analytics solutions for Real-LIfe APplications (DARLI-AP). CEUR Workshop Proceedings
Editorial
Nanni, Mirco; Pelekis, Nikos; Tampakis, Panagiotis; Zeitouni, Karine; Sakr, Mahmoud; Renso, Chiara. (2025) Big Mobility Data Analytics (BMDA). CEUR Workshop Proceedings
Editorial
Shadrooh, Shiva; Nørvåg, Kjetil. (2024) SMoTeF: Smurf money laundering detection using temporal order and flow analysis. Applied intelligence (Boston)
Academic article
Shadrooh, Shiva; Nørvåg, Kjetil. (2024) Datis: data augmentation for trust intensity prediction in incomplete signed networks. Social Network Analysis and Mining
Academic article
Vlachou, Akrivi; Doulkeridis, Christos; Rocha-Junior, Joao B.; Nørvåg, Kjetil. (2023) Decisive skyline queries for truly balancing multiple criteria. Data & Knowledge Engineering
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil; Dam, Thu-Lan. (2021) Density Guarantee on Finding Multiple Subgraphs and Subtensors. ACM Transactions on Knowledge Discovery from Data
Academic article
Dam, Thu-Lan; Chester, Sean; Nørvåg, Kjetil; Duong, Quang-Huy. (2021) Efficient top-k recently-frequent term querying over spatio-temporal textual streams. Information Systems
Academic article
Trattner, Christoph; Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2019) Investigating and predicting online food recipe upload behavior. Information Processing & Management
Academic article
Özdikis, Özer; Ramampiaro, Heri; Nørvåg, Kjetil. (2019) Locality-adapted kernel densities of term co-occurrences for location prediction of tweets. Information Processing & Management
Academic article
Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2018) On Validation and Predictability of Digital Badges’ Influence on Individual Users. Proceedings of the AAAI Conference on Artificial Intelligence
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Applying temporal dependence to detect changes in streaming data. Applied intelligence (Boston)
Academic article
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil; Fournier-Viger, Philippe; Dam, Thu-Lan. (2018) High utility drift detection in quantitative data streams. Knowledge-Based Systems
Academic article
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2017) Exploratory product search using top-k join queries. Information Systems
Academic article
Doulkeridis, Christos; Nørvåg, Kjetil. (2014) A survey of large-scale analytical query processing in MapReduce. The VLDB journal
Academic literature review
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2012) Distributed top-k query processing by exploiting skyline summaries. Distributed and parallel databases
Academic article
Vlachou, Akrivi; Doulkeridis, Christos; Kotidis, Yannis; Nørvåg, Kjetil. (2011) Monochromatic and Bichromatic Reverse Top-k Queries. IEEE Transactions on Knowledge and Data Engineering
Academic article
Hauglid, Jon Olav; Ryeng, Norvald Hegelstad; Nørvåg, Kjetil. (2010) DYFRAM: dynamic fragmentation and replica management in distributed database systems. Distributed and parallel databases
Academic article
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Kotidis, Yannis. (2010) Identifying the Most Influential Data Objects with Reverse Top-k Queries. Proceedings of the VLDB Endowment
Academic article
Rocha-Junior, Joao B.; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2010) Efficient Processing of Top-k Spatial Preference Queries. Proceedings of the VLDB Endowment
Academic article
Doulkeridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2007) DESENT: decentralized and distributed semantic overlay generation in P2P networks. IEEE Journal on Selected Areas in Communications
Academic article

Books

Kanhabua, Nattiya; Blanco, Roi; Nørvåg, Kjetil. (2015) Temporal Information Retrieval. Now Publishers Inc. Now Publishers Inc.
Academic monograph

Part of book/report

Theodoropoulos, George S.; Nørvåg, Kjetil; Doulkeridis, Christos. (2023) Efficient Semantic Similarity Search over Spatio-textual Data. OpenProceedings
Academic chapter/article/Conference paper
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2020) Multiple Dense Subtensor Estimation with High Density Guarantee. IEEE Press
Academic chapter/article/Conference paper
Maropaki, Stella; Chester, Sean; Doulkeridis, Christos; Nørvåg, Kjetil. (2020) Diversifying Top-k Point-of-Interest Queries via Collective Social Reach. ACM Publications
Academic chapter/article/Conference paper
Djenouri, Youcef; Lin, Chun Wei; Nørvåg, Kjetil; Ramampiaro, Heri. (2019) Highly Efficient Pattern Mining Based on Transaction Decomposition. IEEE Press
Academic chapter/article/Conference paper
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2019) Sketching Streaming Histogram Elements using Multiple Weighted Factors. ACM Publications
Academic chapter/article/Conference paper
Özdikis, Özer; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Locality-adapted Kernel Densities for Tweet Localization. ACM Publications
Academic chapter/article/Conference paper
Benetka, Jan; Balog, Krisztian; Nørvåg, Kjetil. (2017) Anticipating Information Needs Based on Check-in Activity. ACM Publications
Academic chapter/article/Conference paper
Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2016) Online Food Recipe Title Semantics: Combining Nutrient Facts and Topics. ACM Publications
Academic chapter/article/Conference paper
Saouk, Mei; Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil. (2016) Efficient processing of top-k joins in MapReduce. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper
Chester, Sean; Gkorgkas, Orestis; Nørvåg, Kjetil. (2016) Top-k Dominating Queries, in Parallel, in Memory. OpenProceedings
Academic chapter/article/Conference paper
Larrain, Santiago; Trattner, Christoph; Parra, Denis; Graells-Garrido, Eduardo; Nørvåg, Kjetil. (2015) Good Times Bad Times: A Study on Recency Effects in Collaborative Filtering for Social Tagging. ACM Publications
Other
Kusmierczyk, Tomasz; Trattner, Christoph; Nørvåg, Kjetil. (2015) Temporality in Online Food Recipe Consumption and Production. ACM Publications
Other
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2015) Finding the Most Diverse Products using Preference Queries. OpenProceedings
Academic chapter/article/Conference paper
Kotsakos, Dimitrios; Lappas, Theodoros; Kotzias, Dimitrios; Gunopulos, Dimitrios; Kanhabua, Nattiya; Nørvåg, Kjetil. (2014) A burstiness-aware approach for document dating. ACM Publications
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Kotidis, Yannis. (2013) Branch-and-bound algorithm for reverse top-k queries. ACM Publications
Academic chapter/article/Conference paper
Ciglan, Marek; Laclavik, Michal; Nørvåg, Kjetil. (2013) On community detection in real-world networks and the importance of degree assortativity. ACM Publications
Academic chapter/article/Conference paper
Rocha-Junior, Joao B.; Nørvåg, Kjetil. (2012) Top-k spatial keyword queries on road networks. ACM Publications
Academic chapter/article/Conference paper
Ciglan, Marek; Nørvåg, Kjetil; Hluchy, Ladislav. (2012) The SemSets model for ad-hoc semantic list search. ACM Publications
Academic chapter/article/Conference paper
Rocha-Junior, Joao B.; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2011) Efficient Execution Plans for Distributed Skyline Query Processing. ACM Publications
Academic chapter/article/Conference paper
Zhang, Xiangliang; Wang, Wei; Nørvåg, Kjetil; Sebag, Michele. (2010) K-AP: Generating Specified K Clusters by Efficient Affinity Propagation. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper
Ciglan, Marek; Nørvåg, Kjetil. (2010) WikiPop: personalized event detection system based on Wikipedia page view statistics. ACM Publications
Academic chapter/article/Conference paper
Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2010) On the selectivity of multidimensional routing indices. ACM Publications
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Kotidis, Yannis; Nørvåg, Kjetil. (2010) Reverse Top-k Queries. IEEE Press
Academic chapter/article/Conference paper
Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2009) Multidimensional Routing Indices for Efficient Distributed Query Processing. Association for Computing Machinery (ACM)
Academic chapter/article/Conference paper
Hauglid, Jon Olav; Nørvåg, Kjetil; Ryeng, Norvald Hegelstad. (2009) Efficient and Robust Database Support for Data-Intensive Applications in Dynamic Environments. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeiridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) On efficient top-k query processing in highly distributed environments. ACM Publications
Academic chapter/article/Conference paper
Hauglid, Jon Olav; Nørvåg, Kjetil. (2008) PROQID: Partial Restarts of Queries in Distributed Databases. Association for Computing Machinery (ACM)
Academic chapter/article/Conference paper
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) Skyline-based Peer-to-Peer Top-k Query Processing. IEEE (Institute of Electrical and Electronics Engineers)
Academic chapter/article/Conference paper

Report

Abedi Firouzjaei, Hassan; Nørvåg, Kjetil; Gupta, Dhruv. (2025) Unveiling Novel Patterns of User Interactions in Online Communities. Doctoral theses at NTNU (223)
Doctoral dissertation

Språkvelger