I am an assistant professor at the Utrecht University department of Sociology. The focus of my research is understanding (online) extremism and threats of violence by using computational linguistics. I hold a PhD from the UCL Department of Security and Crime Science. I aim to develop solutions to better understand and counter radicalisation, extremism, terrorism, and other forms of grievance-fuelled targeted violence. I am also interested in improving research transparency within and beyond the field of crime science.

More: University profile, Bluesky, LinkedIn, Open Science Framework, Google Scholar.

See my website for the Grievance Dictionary an open-source tool for automatic linguistic threat assessment.

Selected publications & pre-prints

• van der Vegt, I., Kleinberg, B., Miotto, M., & Festor, J. (2025). Translating the Grievance Dictionary: a psychometric evaluation of Dutch, German, and Italian versions. Pre-print.
• van der Vegt, I. (2024). The relationship between conspiracy theories and online hate directed at politicians. Tijdschrift voor Criminologie, 66(3). In Dutch.
• van der Vegt, I. (2024). Gender Differences in Abuse: The Case of Dutch Politicians on Twitter. Crime Science. Open Access.
• Clemmow, C., van der Vegt, I., Rottweiler, B., Schumann, S., & Gill, P. (2024). Crowdsourcing Samples for Research on Violent Extremism: A Research Note. Terrorism and Political Violence. Open Access.
• van der Vegt, I., Kleinberg, B., & Gill, P. (2023). Proceed with Caution: On the Use of Computational Linguistics in Threat Assessment. Open Access.
• van der Vegt, I., Kleinberg, B., & Gill, P. (2022). Predicting author profiles from online abuse directed at public figures. Journal of Threat Assessment and Management. Author version.
• van der Vegt, I., Gregory, P., van der Meer, B.B., Yang, E., Kleinberg, B., & Gill, P. (2022). Assessment procedures in anonymously written threats of harm and violence. Journal of Threat Assessment and Management. Author version.
• van der Vegt, I., Mozes, M., Kleinberg, B. & Gill, P.(2021) The Grievance Dictionary: Understanding Threatening Language Use. Behavior Research Methods. Open Access.
• van der Vegt, I., Mozes, M., Gill, P., & Kleinberg, B. (2020). Online influence, offline violence: Language use on YouTube surrounding the ‘Unite the Right’ rally. Journal of Computational Social Science. Open Access.

Brief CV

• 2022-present: Assistant professor, Department of Sociology, Utrecht University
• 2021-2023: Honorary research fellow, Department of Security & Crime Science, University College London
• 2021-2022: Scientific project manager, Research and Documentation Centre, Ministry of Justice and Security (Netherlands)
• 2018-2021: PhD candidate, Department of Security & Crime Science, University College London, supervised by Paul Gill & Bennett Kleinberg
• 2015-2017: Research Master’s degree in Psychology, University of Amsterdam
• 2012-2015: Bachelor of Liberal Arts & Sciences (Psychology + Linguistics), University College Utrecht