The research, plainly
Daniel Ellsberg's urn experiments showed people prefer known odds to unknown odds — even when the unknown option is objectively as good or better. Uncertainty itself is a cost we'll pay real money to avoid.
The receipt: Ellsberg, 1961
What it means for events
Every unanswered question — parking, dress code, who's coming, what happens first, will I be called on — is a tiny tax on attendance and participation. No-shows aren't rejecting your content; they're avoiding your unknowns.
Where to run it
Pre-event comms
The know-before-you-go isn't admin — it's conversion. Answer everything a nervous first-timer would ask, before they ask.
Session design
Tell people the format up front: 'you won't be cold-called; tables discuss first.' Watch participation rise as uncertainty falls.
Executive events
Publish who's in the room (with permission). 'Who else will be there' is the whole decision for senior attendees.
Seen in the wild
Related concepts
Now use it
Score your own event against principles like this one — or make the whole vocabulary official.
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