Lab Guide — Deciding Under Uncertainty

Facilitated exercise · 40 minutes · Fictional ambiguous incident

What this lab is

A facilitated decision exercise built around a fictional ambiguous incident with conflicting information. In groups you will state a risk appetite, run a rapid pre-mortem, and commit to a first action — then defend it against a devil's advocate.

The inject

Brief

An alert suggests possible unauthorised access to a sensitive system. One analyst is confident it is real; another thinks it is a misconfiguration. A partner has hinted at a campaign against your sector, but attribution is unclear. A board meeting is in progress.

Part A — Evidence vs inference (12 min)

Sort what you have

List what you actually know versus what you are inferring.
Name the base rate: how often do alerts like this turn out real?

Part B — Pre-mortem & first move (15 min)

Decide

Run a 60-second pre-mortem: it is a month later and your choice failed — why?
Commit to a reversible first action and say why it is safe if you are wrong.

Part C — Devil's advocate (13 min)

Stress the decision

Appoint one member to argue the opposite. Does your first move survive? Adjust it if the challenge is sound, and note which bias the challenge exposed.

✓ Self-check: your group separated evidence from inference, chose a reversible first action justified under either outcome, and named the specific bias the devil's advocate surfaced.