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Field notes · Founder Effect

Generative agents and the limits of simulation

Two studies examine different uses of language-model agents. Neither establishes an accuracy score for Founder Effect or a prediction of product demand.

Updated 2026-09-07 · 2 min read

A town with 25 agents

Park and colleagues’ 2023 study placed 25 generative agents in a sandbox environment. Their architecture combined stored experiences, reflection and planning. The evaluation examined the believability of individual behavior and social coordination, including the spread of an invitation to a party.

That is a useful example of an architecture for agent interaction. Believable behavior in this setting does not establish reliable purchase predictions for a business. Read the 2023 paper.

Grounding agents in participant information

A separate study by Park and colleagues built agents from interviews, surveys or both involving 1,052 Americans. The evaluation included held-out survey responses, with participants’ own two-week answer consistency used as a benchmark.

The revised paper distinguishes the results of the different input methods. These conditions are important when interpreting its findings. Read the revised paper.

What a result does not establish

A generated demographic sketch differs from the interviews and survey responses of a real participant. A result measured with one input and evaluation setup cannot be assumed to apply to another.

Neither study tested Founder Effect. The reported results are not a general accuracy score for synthetic customers, and this site does not use them to promise a percentage chance of commercial success.

How we use the research

Founder Effect is developing a method that combines source evidence, synthetic persona reactions and a separate challenge to the findings. A generated reaction may suggest an objection worth investigating. It still needs an appropriate check.

The output is a set of hypotheses and possible tests, with the evidence and limitations attached. The software platform is not publicly available.

Read the method and research limitations.

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