CAP: Cross-Ability Preferences to Align Student Simulators for Item Difficulty Prediction

Nigel Fernandez, Alexander Scarlatos, Christopher Ormerod, Andrew Lan


Abstract
We develop CAP, a preference optimization-based method for aligning LLM student simulators to student ability. It constructs preference pairs from IRT ability gaps, training the simulator to generate responses that better reflect prompted ability, enabling simulation-based estimation of open-ended item difficulty.
Anthology ID:
2026.aimecon-main.37
Volume:
Proceedings of the Artificial Intelligence in Measurement and Education Conference (AIME-Con): Full Papers
Month:
October
Year:
2026
Address:
Wyndham Grand Pittsburgh Downtown, Pittsburgh, Pennsylvania, United States
Editors:
Joshua Wilson, Christopher Ormerod, Magdalen Beiting-Parrish
Venue:
AIME-Con
SIG:
Publisher:
National Council on Measurement in Education (NCME)
Note:
Pages:
332–344
Language:
URL:
https://aclanthology.org/2026.aimecon-main.37/
DOI:
Bibkey:
Cite (ACL):
Nigel Fernandez, Alexander Scarlatos, Christopher Ormerod, and Andrew Lan. 2026. CAP: Cross-Ability Preferences to Align Student Simulators for Item Difficulty Prediction. In Proceedings of the Artificial Intelligence in Measurement and Education Conference (AIME-Con): Full Papers, pages 332–344, Wyndham Grand Pittsburgh Downtown, Pittsburgh, Pennsylvania, United States. National Council on Measurement in Education (NCME).
Cite (Informal):
CAP: Cross-Ability Preferences to Align Student Simulators for Item Difficulty Prediction (Fernandez et al., AIME-Con 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.aimecon-main.37.pdf