Using sets of LLM personas as stand-ins for real human populations is a key challenge in LLM-based social simulation. Recent methods use LLMs to generate personas from real social media histories or via structured sampling, and align them to a reference distribution such as Big Five psychometrics. But imagine a synthetic population whose Big Five personality profile is statistically indistinguishable from that of a real survey population. Ask these personas for their opinions on a policy, or observe how they actually behave in a simulated decision, and the match may fall apart: aligning a persona set to one reference distribution guarantees nothing about the others, and recent evidence shows that a persona's self-reported traits often dissociate from its behaviour. Instead of aligning the persona set to a single psychometric distribution, we aim to align it to multiple reference distributions simultaneously — spanning psychometric, opinion, and behavioural responses — and study whether jointly aligned persona sets generalize better to distributions and simulation tasks they were never aligned on. The team is co-led by Dr. Aditya Joshi, a Senior Lecturer in Natural Language Processing (NLP), and Haokai Zhao, a PhD student, in the UNSW-NLP research group.

The ideal student will have strong programming skills in Python. A good grounding in statistics would be highly regarded.

School

Computer Science and Engineering

Research Area

LLM | Natural language processing

Suitable for recognition of Work Integrated Learning (industrial training)?

No

The student will be a part of the natural language processing (NLP) research group consisting of postdocs, software engineers and PhD students. The student will have access to typical computing facilities at UNSW.

  1. Reproduction of existing persona synthesis pipelines.
  2. A benchmark of existing persona sets on survey and behavioural response distributions.
  3. Develop new methods for synthesizing persona sets that generalize to unseen survey and behavioral distributions.
  4. Well-documented code with accompanying documentation.
  5. A report in a form suitable for a research paper.