Portrait missing

Johannes ­ Prager [✓]



Room: F112
Hauptstraße 47
69117 Heidelberg

  • impression formation from incomplete samples
  • ecological and psychological determinants of judgment and decision making
  • adaptivity in cost-benefit trade-offs
  • applied statistical methodology and replication science
  • application of decision making theories in sustainable behavior


Recent courses

Below you find a list of courses I am going to teach this semester (Wintersemester 2021/22).

Please refer to the lecture index (LSF) for past courses..

2016 - present: Heidelberg University, PhD Student

February 2020 - May 2020 visiting PhD Student at Universitat Pompeu Fabra (Barcelona)

2014 - 2016 University of Mannheim, Master of Science

2011 - 2014 University of Mannheim, Bachelor of Science


Prager, J., & Fiedler, K. (in press) Forming Impressions from Self-Truncated Samples of Traits - Interplay of Thurstonian and Brunswikian Sampling Effects. Journal of Personality and Social Psychology

Fiedler, K., McCaughey, L., & Prager, J. (2021). Quo vadis, methodology? The key role of manipulation checks for validity control and quality of science. Perspectives on Psychological Science, 16 (4), 816-826.


Fiedler, K., McCaughey, L., Prager, J., Eichberger, J., & Schnell, K. (2020). Speed-accuracy trade-offs in sample-based decisions. Journal of Experimental Psychology: General.


Prager, J., Krueger, J. I., & Fiedler, K. (2018). Towards a deeper understanding of impression formation—New insights gained from a cognitive-ecological perspective. Journal of Personality and Social Psychology, 115 (3), 379-397.

Fiedler, K., & Prager, J. (2018). The Regression Trap and Other Pitfalls of Replication Science—Illustrated by the Report of the Open Science Collaboration. Basic and Applied Social Psychology, 40 (3), 115-124.