Willem Sleegers

Senior Behavioral Scientist at Rethink Priorities


Employment

2021-current Senior Behavioral Scientist at Rethink Priorities
2018-2021 Tenure track Assistant Professor in social psychology at Tilburg University
2016-2018 Fixed term Assistant Professor in social psychology at Tilburg University
2012-2016 Graduate student on the topic of physiological arousal in meaning maintenance at Tilburg University
2011-2012 Student assistant during my Research Master: Behavioral Science at Nijmegen University
2012-2013 Programmer of experimental psychology tasks for FrieslandCampina
2007-2010 Media analyst for Report International

Education

2012-2016 Graduate student at Tilburg University supervised by prof. dr. Ilja van Beest and dr. Travis Proulx
2012-2016 Student member of the Kurt Lewin Institute (KLI)
2010-2012 Research Master Behavioural Science at Nijmegen University
2010-2012 Expert track in data-analysis
2007-2010 Psychology BSc. at Nijmegen University
2007-2010 Honours Program of Psychology at Nijmegen University

Publications

In preparation

van Leeuwen, F., Jaeger, B., Sleegers, W. W. A., & Petersen, M. B. (in prep.) Pathogen avoidance and conformity: Salient infectious disease does not increase conformity.
Jaeger, B., Sleegers, W. W. A., Stern, J., Penke, L., & Jones, A. (in prep.) The accuracy and meta-accuracy of personality impressions from faces.
Sleegers, W. W. A. & Jaeger, B. (in prep.) The social cost of correcting others.

Preprints

Jaeger, B., Sleegers, W. W. A. (2020) Racial discrimination in the sharing economy: Evidence from Airbnb markets across the world. https://psyarxiv.com/qusxf
Breznau, N., et al. (2021) The Crowdsourced Replication Initiative: Investigating Immigration and Social Policy Preferences. Executive Report. https://osf.io/preprints/socarxiv/6j9qb/
Breznau, N., et al. (2021) How many replicators does it take to achieve reliability? Investigating researcher variability in a crowdsourced replication. https://osf.io/preprints/socarxiv/j7qta/

Stage-1 accepted manuscripts

2021 Sleegers, W. W. A., Vaidis, D. (shared first author) et al. (2021). A multi-lab replication of the induced compliance paradigm of cognitive dissonance. Advances in Methods and Practices in Psychological Science. https://osf.io/52wpj

Peer-reviewed journals

2021 Pronk, T. M., Bogaers, R. I., Verheijen, M. S., Sleegers, W. W. A. (in press). Pupil size predicts partner choices in online dating. Social Cognition.
2021 Evans, A. M., Kogler, C., & Sleegers, W. W. A. (in press). No effect of synchronicity in online social dilemma experiments: A registered report. Judgment and Decision Making.
2021 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
2021 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
2021 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
2020 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
2020 Evans, A., Sleegers, W. W. A., & Mlakar, Ž. (2020). Individual differences in receptivity to scientific bullshit. Judgment and Decision Making, 15(3), 401-412.
2020 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
2019 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
2019 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
2019 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
2018 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
2017 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
2017 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
2015 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
2015 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

2019 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

2017 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

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

Websites

My personal website where I blog about (some of) my research.https://www.willemsleegers.com
The tidystats website, a support website for my tidystats software.https://www.tidystats.io

Presentations

Invited talks

2021 Sleegers, W. W. A. (2021, March). tidystats. Talk for a research group at the Ministry of Defence.
2021 Sleegers, W. W. A. (2021, February). tidystats. Talk for the BSI at Nijmegen University.
2021 Sleegers, W. W. A. (2021, February). Cognitive dissonance RRR. Lab meeting at Cardiff University.
2018 Sleegers, W. W. A. (2018, December). Pupillometry and psychology. Colloquium presentation for the Laboratoire de Psychologie Sociale department at Paris Descartes University.
2018 Sleegers, W. W. A. (2018, October) tidystats. Colloquium presentation for the Methodology and Statistics department at Leiden University.
2018 Sleegers, W. W. A. (2018, March) tidystats. Colloquium presentation for the MTO department at Tilburg University.
2017 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.
2017 Sleegers, W. W. A. (2017, March). Pupillometry and psychological processes. Colloquium presentation at Cardiff University.
2015 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

2019 Sleegers, W. W. A. (2019, July) tidystats. Lightning talk at the SIPS conference, Rotterdam, the Netherlands.
2019 Sleegers, W. W. A. & Jaeger, B. (2019, December) The Social Cost of Correcting Others. Talk at the ASPO conference, Wageningen, the Netherlands.
2018 Sleegers, W. W. A. (2018, June) tidystats. Lightning talk at the SIPS conference, Grand Rapids, MI.
2017 Sleegers, W. W. A. (2017, August). oTree for social scientists. Presentation at the TIBER conference, Tilburg, the Netherlands.
2016 Sleegers, W. W. A., Proulx, T. & Van Beest (2016, December). Evidence of aversive arousal motivating compensatory behavior. Presentation at ASPO conference, Leiden, the Netherlands.
2014 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.
2014 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.
2014 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

2019 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

2017 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.
2016 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.
2015 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.
2015 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.
2014 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

2017 Sleegers, W. W. A., & Wagemans, F. M. A. (2017, November). The psychology behind eye tracking. Presentation organized by the Academic Forum of Tilburg University.
2017 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 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, Journal of Cognitive Psychology.

Teaching

Courses

2017-2021 Social Psychology
2016-2021 Attitudes and Advertising
2019-2021 Understanding Data with R
2015/2017/2019 Research Master: Experimental Research and Meta-Analysis
2016-2021 Course in R software
2019-2021 Understanding Data with R

Seminars

2012-2017 Social Psychology
2015-2016 Introduction and History of Psychology
2014-2015 Cultural Psychology
2013-2015 Academic Skills
2012-2013 Group Skills

Individual lectures

2016 Social Psychology
2014 Introduction and History of Psychology on intrapersonal conflict
2013 Introduction to Social Psychology for prospective students

Supervision

2021 Research Master in Psychology theses
2016-2021 Master in Psychology theses
2013-2021 Bachelor in Psychology theses
2012-2018 Research Skills in Psychology

Coordination

2014-2021 Social Psychology
2016-2021 Attitudes and Advertising

Other

2013-2021 An introduction to R; part of the Kurt Lewin Institute course program

Technical skills

Statistics

R: A free software environment for statistical computing and graphics
SPSS: A proprietary data analysis program

Programming

Python: A cross-platform procedural programming language
HTML: Markup language for creating web pages and web applications
CSS: Markup language for styling web pages and web applications
JavaScript: A programming language for creating web applications
Django: A high-level Python Web framework
Hugo: A static HTML and CSS website generator

Experimental design

Millisecond’s Inquisit: Stimulus delivery and experimental design software
oTree: Framework based on Python and Django to create standard and interactive online psychological experiments
Tobii Studio and Tobii Studio Extensions for E-prime: software to run eye tracker experiments using Tobii eye trackers
Psychology Software Tool’s E-Prime: Stimulus delivery and experimental design software
Adobe’s Authorware: Stimulus delivery and experimental design software. This has been discontinued, please do not make me use it
Neurobehavioural Systems’ Presentation®: A stimulus delivery and experimental control program for neuroscience