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

Abedi Firouzjaei, Hassan; Nørvåg, Kjetil; Gupta, Dhruv. (2025) Unveiling Novel Patterns of User Interactions in Online Communities. Norges teknisk-naturvitenskapelige universitet
Doctoral thesis

2024

Shadrooh, Shiva; Nørvåg, Kjetil. (2024) SMoTeF: Smurf money laundering detection using temporal order and flow analysis. Applied Intelligence - The International Journal of Research on Intelligent Systems for Real Life Complex Problems
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.
Academic chapter
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.
Academic chapter
Maropaki, Stella; Chester, Sean; Doulkeridis, Christos; Nørvåg, Kjetil. (2020) Diversifying Top-k Point-of-Interest Queries via Collective Social Reach.
Academic chapter

2019

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
Djenouri, Youcef; Lin, Chun Wei; Nørvåg, Kjetil; Ramampiaro, Heri. (2019) Highly Efficient Pattern Mining Based on Transaction Decomposition.
Academic chapter
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2019) Sketching Streaming Histogram Elements using Multiple Weighted Factors.
Academic chapter

2018

Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Applying temporal dependence to detect changes in streaming data. Applied Intelligence - The International Journal of Research on Intelligent Systems for Real Life Complex Problems
Academic article
Özdikis, Özer; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Locality-adapted Kernel Densities for Tweet Localization.
Academic chapter
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
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

2017

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

2016

Chester, Sean; Gkorgkas, Orestis; Nørvåg, Kjetil. (2016) Top-k Dominating Queries, in Parallel, in Memory.
Academic chapter
Saouk, Mei; Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil. (2016) Efficient processing of top-k joins in MapReduce.
Academic chapter
Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2016) Online Food Recipe Title Semantics: Combining Nutrient Facts and Topics.
Academic chapter

2015

Kanhabua, Nattiya; Blanco, Roi; Nørvåg, Kjetil. (2015) Temporal Information Retrieval. Now Publishers Inc.
Academic monograph
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2015) Finding the Most Diverse Products using Preference Queries.
Academic chapter

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.
Academic chapter

2013

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

2012

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

2011

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
Rocha-Junior, Joao B.; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2011) Efficient Execution Plans for Distributed Skyline Query Processing.
Academic chapter

2010

Zhang, Xiangliang; Wang, Wei; Nørvåg, Kjetil; Sebag, Michele. (2010) K-AP: Generating Specified K Clusters by Efficient Affinity Propagation.
Academic chapter
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.
Academic chapter
Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2010) On the selectivity of multidimensional routing indices.
Academic chapter
Vlachou, Akrivi; Doulkeridis, Christos; Kotidis, Yannis; Nørvåg, Kjetil. (2010) Reverse Top-k Queries.
Academic chapter
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
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

Hauglid, Jon Olav; Nørvåg, Kjetil; Ryeng, Norvald Hegelstad. (2009) Efficient and Robust Database Support for Data-Intensive Applications in Dynamic Environments.
Academic chapter
Doulkeridis, Christos; Vlachou, Akrivi; Nørvåg, Kjetil; Kotidis, Yannis; Vazirgiannis, Michalis. (2009) Multidimensional Routing Indices for Efficient Distributed Query Processing.
Academic chapter

2008

Hauglid, Jon Olav; Nørvåg, Kjetil. (2008) PROQID: Partial Restarts of Queries in Distributed Databases.
Academic chapter
Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) Skyline-based Peer-to-Peer Top-k Query Processing.
Academic chapter
Vlachou, Akrivi; Doulkeiridis, Christos; Nørvåg, Kjetil; Vazirgiannis, Michalis. (2008) On efficient top-k query processing in highly distributed environments.
Academic chapter

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

Doulkeridis, Christos; Nørvåg, Kjetil. (2014) A survey of large-scale analytical query processing in MapReduce. The VLDB journal
Academic literature review
Trattner, Christoph; Kusmierczyk, Tomasz; Nørvåg, Kjetil. (2019) Investigating and predicting online food recipe upload behavior. Information Processing & Management
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
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
Duong, Quang-Huy; Ramampiaro, Heri; Nørvåg, Kjetil. (2018) Applying temporal dependence to detect changes in streaming data. Applied Intelligence - The International Journal of Research on Intelligent Systems for Real Life Complex Problems
Academic article
Shadrooh, Shiva; Nørvåg, Kjetil. (2024) SMoTeF: Smurf money laundering detection using temporal order and flow analysis. Applied Intelligence - The International Journal of Research on Intelligent Systems for Real Life Complex Problems
Academic article
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
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
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
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
Gkorgkas, Orestis; Vlachou, Akrivi; Doulkeridis, Christos; Nørvåg, Kjetil. (2017) Exploratory product search using top-k join queries. Information Systems
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
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
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
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.
Academic monograph

Part of book/report

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

Student thesis or dissertation

Abedi Firouzjaei, Hassan; Nørvåg, Kjetil; Gupta, Dhruv. (2025) Unveiling Novel Patterns of User Interactions in Online Communities. Norges teknisk-naturvitenskapelige universitet
Doctoral thesis

Språkvelger