── ── Mental model
Nudge Theory
People procrastinate on retirement savings, skip vaccine appointments, and leave privacy settings on dangerous defaults — not from ignorance, but because the choice environment works against them. Nudge theory (Thaler & Sunstein) treats choice architecture — defaults, framing, social norms, friction — as the decisive variable. A nudge alters behavior in a predictable way without forbidding options or changing economic…
Run Nudge Theory on a real problem
Bring something you're actually deciding — free, in the browser.
How it works
Run the EAST Nudge Design. Behavior first, barrier second, mechanism third, test fourth.
Stop-rule: If you cannot name a specific, observable, measurable target behavior, stop. "Improve engagement" is not a target behavior.
1. Define the target behavior precisely. Exact action, population, and baseline rate. 2. Diagnose the barrier (EAST). E — Easy (friction/complexity/defaults); A — Attractive (salience/framing/loss aversion); S — Social (missing norm info); T — Timely (wrong trigger moment). 3. Match barrier to mechanism. Easy → default redesign, friction removal; Attractive → loss framing, salience; Social → descriptive norm message; Timely → implementation-intention prompt or event trigger. 4. Design the nudge. Specify exact wording, default state, timing, visual. Check: (a) free choice preserved? (b) transparent — would disclosing it collapse the effect? (c) serves the chooser, not the designer? 5. Design the test. Randomized control: define primary metric, minimum detectable effect, sample size, resolution date. 6. Plan for scale and decay. Define monitoring cadence and re-evaluation trigger.
When to use it
- user says 'nudge,' 'default,' 'opt-in vs opt-out,' 'choice architecture,' or 'why do people know they should but don't?'
- user has a behavior gap between intent and action
- user is designing product onboarding, policy enrollment, or public health interventions and wants to change behavior without mandates or incentives
When not to use it
When the decision is routine and reversible, applying a formal method costs more than it returns.
Worked example
401(k) Automatic Enrollment and the Pension Protection Act (2006)
A documented, peer-reviewed case — not a pop-culture parable.
Install this skill (free, MIT)
npx skills add deciqAI/knowledge-skillsUseful? Star the repo — stars help other builders find it.
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