CV

Willem W. A. Sleegers

Currently

I’m a Senior Behavioral Scientist at Rethink Priorities. As part of the survey and data analysis team, I conduct research on attitude assessments and attitude change, using surveys and experimental designs. Before joining Rethink Priorities, I was an assistant professor in the Department of Social Psychology at Tilburg University, where I maintain an academic affiliation.

Employment

Education

Skills

Research

• Survey and experimental design
• Lab and online participant recruitment

Statistics

• Advanced statistical modelling (e.g., multilevel (Bayesian) regression, meta-analysis, factor analysis)
• Data cleaning and preprocessing
• Data visualization and reporting

Software

• R
• RStudio
• VS Code
• Positron
• SPSS

Programming

• HTML, CSS, JavaScript, React, WebR, Python
• CSS
• JavaScript
• React
• WebR
• Python

Survey platforms

• Qualtrics
• SurveyMonkey
• oTree
• Inquisit

Publications

Preprints

• Gruetzemacher, R., Pilditch, T. D., Liang, H., Manning, C., Gates, V., Moss, D., Elsey, J. W. B., Sleegers, W. W. A., & Kilian, K. (2024). Implications for governance in public perceptions of societal-scale AI risks. arXiv. https://doi.org/10.48550/arXiv.2406.06199
• Sleegers, W., Moss, D., McAuliffe, W., Reinstein, D., & Waldhorn, D. R. (2023). Measuring attitudes towards wild animal welfare: The Wild Animal Welfare Scale. OSF Preprints. https://doi.org/10.31219/osf.io/qfz73

Peer-reviewed journals

• Kip, A., Erle, T. M., Sleegers, W. W. A., & van Beest, I. (2025). Choice availability and incentive structure determine how people cope with ostracism. Journal of Experimental Social Psychology, 117, 104707. https://doi.org/10.1016/j.jesp.2024.104707
• Rahal, R.-M., Siebers, T., Sleegers, W. W. A., & Van Beest, I. (2024). Your lies don’t leave me cold: Assessing direct, indirect and physiological measures of lie detection. Acta Psychologica, 251, 104548. https://doi.org/10.1016/j.actpsy.2024.104548
• Kip, A., Erle, T. M., Sleegers, W. W. A., & Van Beest, I. (2023). Emotions and behavioral intentions in response to ostracism attributed to a perceived lack of warmth versus competence. Group Processes & Intergroup Relations, 13684302231212853. https://doi.org/10.1177/13684302231212853
• Sleegers, W. W. A., Van Leeuwen, F., Ross, R. M., DeMarree, K. G., Van Beest, I., Priolo, D., Martinie, M.-A., Morvinski, C., Verschuere, B., & Vaidis, D. C. (2024). When replication fails: What to conclude and not to conclude? Advances in Methods and Practices in Psychological Science, 7(4), 25152459241268197. https://doi.org/10.1177/25152459241268197
• Vaidis, D. C., Sleegers, W. W. A., Van Leeuwen, F., DeMarree, K. G., Sætrevik, B., Ross, R. M., Schmidt, K., Protzko, J., Morvinski, C., Ghasemi, O., Roberts, A. J., Stone, J., Bran, A., Gourdon-Kanhukamwe, A., Gunsoy, C., Moussaoui, L. S., Smith, A. R., Nugier, A., Fayant, M.-P., … Priolo, D. (2024). A multilab replication of the induced-compliance paradigm of cognitive dissonance. Advances in Methods and Practices in Psychological Science, 7(1), 25152459231213375. https://doi.org/10.1177/25152459231213375
• Jaeger, B., Sleegers, W. W., Stern, J., Penke, L., & Jones, A. L. (2024). Testing perceivers’ accuracy and accuracy awareness when forming personality impressions from faces. European Journal of Personality, 08902070231225728. https://doi.org/10.1177/08902070231225728
• Ren, D., Wesselmann, E. D., Loh, W. W., van Beest, I., van Leeuwen, F., & Sleegers, W. W. A. (2023). Do cues of infectious disease shape people’s affective responses to social exclusion? Emotion, 23(4), 997–1010. https://doi.org/10.1037/emo0001157
• van Leeuwen, F., Jaeger, B., Sleegers, W. W. A., & Petersen, M. B. (2023) Do experimental manipulations of pathogen avoidance motivations influence conformity? Personality & Social Psychology Bulletin. https://doi.org/10.1177/01461672231160655
• Jaeger, B., & Sleegers, W. W. A. (2023). Racial disparities in the sharing economy: Evidence from more than 100,000 Airbnb hosts across 14 countries. Journal of the Association for Consumer Research, 8(1), 33–46. https://doi.org/10.1086/722700
• Stavrova, O., Evans, A. M., Sleegers, W. W. A., & van Beest, I. (2022) Examining the accuracy of lay beliefs about the effects of personality on prosocial behavior. Journal of Behavioral Decision Making, 1-19. https://doi.org/10.1002/bdm.2282
• Breznau, N., Rinke, E. M., Wuttke, A., Nguyen, H. H. V., Adem, M., Adriaans, J., Alvarez-Benjumea, A., Andersen, H. K., Auer, D., Azevedo, F., Bahnsen, O., Balzer, D., Bauer, G., Bauer, P. C., Baumann, M., Baute, S., Benoit, V., Bernauer, J., Berning, C., Berthold, A., … Żółtak, T. (2022). Observing many researchers using the same data and hypothesis reveals a hidden universe of uncertainty. Proceedings of the National Academy of Sciences of the United States of America, 119(44), e2203150119. https://doi.org/10.1073/pnas.2203150119
• Hoogeveen, S., Sarafoglou, A., Aczel, B., Aditya, Y., Alayan, A. J., Allen, P. J., Altay, S., Alzahawi, S., Amir, Y., Anthony, F.-V., Kwame Appiah, O., Atkinson, Q. D., Baimel, A., Balkaya-Ince, M., Balsamo, M., Banker, S., Bartoš, F., Becerra, M., Beffara, B., … Wagenmakers, E.-J. (2022). A many-analysts approach to the relation between religiosity and well-being. Religion, Brain & Behavior, 1–47. https://doi.org/10.1080/2153599X.2022.2070255
• Pronk, T. M., Bogaers, R. I., Verheijen, M. S., Sleegers, W. W. A. (2021). Pupil size predicts partner choices in online dating. Social Cognition.
• Evans, A. M., Kogler, C., & Sleegers, W. W. A. (2021). No effect of synchronicity in online social dilemma experiments: A registered report. Judgment and Decision Making, 16(4), pp. 823 - 843. https://doi.org/10.1017/S1930297500008007
• Van Osch, Y., & Sleegers, W. W. A. (2021). Replicating and reversing the group attractiveness effect: Relatively unattractive groups are perceived as less attractive than the average attractiveness of their members. Acta Psychologica, 217, 103331. https://.doi.org/10.1016/j.actpsy.2021.103331
• Brandt, M., Sleegers, W. W. A. (2021) Evaluating belief system networks as a theory of political belief system dynamics, 25(2), 159-185. https://doi.org/10.1177/1088868321993751
• Jones, B. C., DeBruine, L. M., Flake, J. K., et al. (2021) To which world regions does the valence–dominance model of social perception apply? Nature Human Behavior, 5, 159–169. https://doi.org/10.1038/s41562-020-01007-2
• Sleegers, W. W. A., Proulx, T., & van Beest, I. (2020) Pupillometry and hindsight bias: Physiological arousal predicts compensatory behavior. Social Psychological and Personality Science. https://doi.org/10.1177/1948550620966153
• Evans, A., Sleegers, W. W. A., & Mlakar, Ž. (2020). Individual differences in receptivity to scientific bullshit. Judgment and Decision Making, 15(3), 401-412.
• Jaeger, B., Sleegers, W. W. A., & Evans, A. M. (2020). Automated classification of demographics from face images: A tutorial and validation. Social and Personality Psychology Compass, 14(3). https://doi.org/10.1111/spc3.12520
• Sleegers, W. W. A., Proulx, T., & van Beest, I. (2019). Confirmation bias and misconceptions: Pupillometric evidence for a confirmation bias in misconceptions feedback. Biological Psychology, 145, 76–83. https://doi.org/10.1016/j.biopsycho.2019.03.018
• Bender, M., van Osch, Y., Sleegers, W. W. A., & Ye, M. (2019). Social support benefits psychological adjustment of international students: Evidence from a meta-analysis. Journal of Cross-Cultural Psychology, 50(7), 827–847. https://doi.org/10.1177/0022022119861151
• Van ‘t Veer, A. E., & Sleegers, W. W. A. (2019). Psychology data from an exploration of the effect of anticipatory stress on disgust vs. Non-disgust related moral judgments. Journal of Open Psychology Data, 7(1), 1. https://doi.org/10.5334/jopd.43
• Jaeger, B., Sleegers, W. W. A., Evans, A. M., Stel, M., & van Beest, I. (2018). The effects of facial attractiveness and trustworthiness in online peer-to-peer markets. Journal of Economic Psychology. https://doi.org/https://doi.org/10.1016/j.joep.2018.11.004
• Proulx, T., Sleegers, W. W. A., & Tritt, S. (2017). The expectancy bias: Expectancy-violating faces evoke earlier pupillary dilation than neutral or negative faces. Journal of Experimental Social Psychology, 70, 69-79. https://doi.org/10.1016/j.jesp.2016.12.003
• Sleegers, W. W. A., Proulx, T., & van Beest, I. (2017). The social pain of Cyberball: Decreased pupillary reactivity to exclusion cues. Journal of Experimental Social Psychology, 69, 187–200. https://doi.org/10.1016/j.jesp.2016.08.004
• Sleegers, W. W. A., Proulx, T., & van Beest, I. (2015). Extremism reduces conflict arousal and increases values affirmation in response to meaning violations. Biological Psychology, 108, 126–131. https://doi.org/10.1016/j.biopsycho.2015.03.012
• Sleegers, W. W. A., & Proulx, T. (2015). The comfort of approach: Self-soothing effects of behavioral approach in response to meaning violations. Frontiers in Psychology, 5, 1–10. https://doi.org/10.3389/fpsyg.2014.01568

Book chapters

• van Beest, I., & Sleegers, W.W.A (2019). Physiostracism: A case for non-invasive measures of arousal in ostracism research. In S. C. Rudert, R. Greifeneder, & K. D. Williams (Eds.), Current directions in ostracism, social exclusion and rejectionresearch. Routledge. https://doi.org/10.4324/9781351255912

Book chapters

• van Beest, I., & Sleegers, W.W.A (2019). Physiostracism: A case for non-invasive measures of arousal in ostracism research. In S. C. Rudert, R. Greifeneder, & K. D. Williams (Eds.), Current directions in ostracism, social exclusion and rejectionresearch. Routledge. https://doi.org/10.4324/9781351255912

Dissertation

• Sleegers, W. W. A. (2017). Meaning and pupillometry: The role of physiological arousal in meaning maintenance (Doctoral dissertation). Retrieved from https://pure.uvt.nl/portal/en/publications/meaning-and-pupillometry(20680e63-e785-43d0-a3ae-e97b26de5f05).html

Software

• Sleegers, W. W. A. (2020). tidystats: Save output of statistical tests (Version 0.5) [Computer software]. https://doi.org/10.5281/zenodo.4041859
• Sleegers, W. W. A. (2020). tidystats (Version 1) [Computer software]. https://doi.org/10.5281/zenodo.4434634

Presentations

Invited talks

• Sleegers, W. W. A. (2024, February). A Multi-Lab Replication of the Induced Compliance Paradigm of Cognitive Dissonance. Colloquium presentation for the Social Psychology department of Tilburg University.
• Sleegers, W. W. A. (2024, January). The Wild Animal Welfare scale. Talk for a research group at the Global Priorities Institute at Oxford University.
• Sleegers, W. W. A. (2021, March). tidystats. Talk for a research group at the Ministry of Defence.
• Sleegers, W. W. A. (2021, February). tidystats. Talk for the BSI at Nijmegen University.
• Sleegers, W. W. A. (2021, February). Cognitive dissonance RRR. Lab meeting at Cardiff University.
• Sleegers, W. W. A. (2018, December). Pupillometry and psychology. Colloquium presentation for the Laboratoire de Psychologie Sociale department at Paris Descartes University.
• Sleegers, W. W. A. (2018, October) tidystats. Colloquium presentation for the Methodology and Statistics department at Leiden University.
• Sleegers, W. W. A. (2018, March) tidystats. Colloquium presentation for the MTO department at Tilburg University.
• Sleegers, W. W. A. (2017, December). Meaning and pupillometry: The role of physiological arousal in meaning maintenance. Presentation at the ASPO conference as part of receiving the best ASPO dissertation award.
• Sleegers, W. W. A. (2017, March). Pupillometry and psychological processes. Colloquium presentation at Cardiff University.
• Sleegers, W. W. A., Proulx, T. & Van Beest, I. (2015, October). Capturing the physiological response to meaning violations: An eye tracker approach. Colloquium presentation at Tilburg University.

Conference presentations

• Sleegers, W. A. A. (2024, August). Personality and the Wild Animal Welfare Scale. Talk at the European Conference on Personality, Berlin, Germany.
• Sleegers, W. A. A. (2024, July). Wild Animal Welfare: Using Surveys to Hopefully Help Wild Animals. Talk at EAGx, Utrecht, the Netherlands.
• Sleegers, W. W. A. (2023, September). Measuring And Understanding People’s Attitudes Towards Wild Animal Welfare. Talk at the Fauna Connections conference organized by Faunalytics.
• Sleegers, W. W. A. (2023, June). The Wild Animal Welfare scale. Talk at the Animal Advocacy Conference, Canterbury, the UK.
• Sleegers, W. W. A. (2019, July). tidystats. Lightning talk at the SIPS conference, Rotterdam, the Netherlands.
• Sleegers, W. W. A. & Jaeger, B. (2019, December). The Social Cost of Correcting Others. Talk at the ASPO conference, Wageningen, the Netherlands.
• Sleegers, W. W. A. (2018, June). tidystats. Lightning talk at the SIPS conference, Grand Rapids, MI.
• Sleegers, W. W. A. (2017, August). oTree for social scientists. Presentation at the TIBER conference, Tilburg, the Netherlands.
• Sleegers, W. W. A., Proulx, T. & Van Beest (2016, December). Evidence of aversive arousal motivating compensatory behavior. Presentation at ASPO conference, Leiden, the Netherlands.
• Proulx, T. & Sleegers, W. W. A. (2014, May). Meaning Maintenance Model: Towards a unified account of threat-compensation behaviors. Presentation at KLI conference, Zeist, the Netherlands.
• Sleegers, W. W. A., Proulx, T., & Van Beest (2014, December). Cyberball and eye tracking: Support for the numbing hypothesis of social exclusion. Presentation at ASPO 2014, Groningen, the Netherlands.
• Sleegers, W. W. A., Proulx, T., & Van Beest (2014, July). Ostracism and eye tracking. Presentation at EASP preconference on threat regulation, Amsterdam, the Netherlands.

Small meetings

• Sleegers, W. W. A. (2019, November) Addressing Incorrect and Incomplete Statistics Reporting (with tidystats). Talk at the meta-research day at Tilburg University, the Netherlands.

Poster presentations

• Sleegers, W. W. A. (2017, July). Pupillometry and psychology: Pupillometry as an experimental tool for psychologists. Poster session presented at the Ostracism, Social Exclusion, and Rejection conference, Vitznau, Switzerland.
• Sleegers, W. W. A., Proulx, T., & Van Beest (2016, January). Ostracism and eye tracking: Decreased pupillary reactivity to exclusion cues. Poster session presented at the SPSP conference, San Diego.
• Sleegers, W. W. A., Proulx, T., & Van Beest (2015, December). Meaning and misconceptions: The effect of error feedback and commitment towards misconceptions on pupil size. Poster session presented at ASPO conference, Amsterdam.
• Sleegers, W. W. A., Proulx, T. & Van Beest (2015, March). Cyberball and eye tracking: Support for the numbing hypothesis of social exclusion. Poster session presented at ICPS conference, Amsterdam, the Netherlands.
• Sleegers, W. W. A., Proulx, T, & Van Beest, I. (2014, May). Extremism and the response to meaning threats: Extremism reduces pupillary response to threat and increases affirmation of values. Poster session presented at the KLI conference, Zeist, the Netherlands.

Valorization presentations

• Sleegers, W. W. A., & Wagemans, F. M. A. (2017, November). The psychology behind eye tracking. Presentation organized by the Academic Forum of Tilburg University.
• Wagemans, F. M. A., & Sleegers, W. W. A. (2017, June). Waar walg jij van? Presentation at Mundial festival on attentional processes and disgust sensitivity using eye tracking.

Journals

I have reviewed for Behavioural Processes, Biological Psychology, British Journal of Psychology, British Journal of Social Psychology, Collabra, European Journal of Social Psychology, Group Processes & Intergroup Relations, International Journal of Psychology, International Review of Social Psychology, Journal of Consumer Behaviour, Journal of Experimental Social Psychology, Journal of Social and Personal Relationships, Personality and Social Psychology Bulletin, PLOS ONE, Self and Identity, Social Cognition, Social Influence, Social Psychology, Current Psychology, and Journal of Cognitive Psychology.

I'm a consulting editor for the Psychology of Human-Animal Intergroup Relations (PHAIR) journal.

Teaching

Courses

Seminars

Individual lectures

Supervision

Coordination

Other