Incentive molecules by combination

A visible year-long grid of contributions makes consistency itself a status signal. Identity does the heavy lifting.

Start with a goal so small it's embarrassing not to do (one push-up). Self-perception updates: 'I'm someone who works out.'

'Don't buy this jacket' positions buying as identity-affirming, not consumption. Sales went up.

Referrers get status + scarce perks (factory tour, free supercharging), not cash. Identity beats discount.

The 'I Voted' sticker is the cheapest civic incentive ever invented: a wearable identity signal that recruits future voters.

Pre-commit future raises to retirement contributions. Defeats present bias by moving the cost to a future self who hasn't earned the money yet.

Source: Thaler & Benartzi (2004)

Texts that ask 'When and where will you get your shot?' lift vaccination rates 4–11% over generic reminders.

Moving the EV credit from tax-time to dealership lifts uptake significantly — same dollars, different timing.

Switching the default from opt-in to opt-out lifts donor rates from ~15% to ~90% with no change in stated preferences.

Source: Johnson & Goldstein (2003)

Putting fruit at eye level and sugary drinks behind glass increases healthy purchases 15–25% without removing options.

Flipping the default to 'enrolled at 3%' lifts participation from ~50% to ~90% across income bands.

Source: Madrian & Shea (2001)

A visible streak counter + loss-aversion freeze + push-notification trigger creates near-daily return behavior.

Pledge money to an anti-charity if you miss a goal. Loss aversion + public stake makes follow-through 2–3× more likely.

Source: stickK.com / Karlan, Ayres

A photo + name of one child outperforms statistics about millions. Emotion compresses; numbers don't.

Source: Slovic et al.

Aggressive per-employee account quotas + tournament ranking + no ethics counter-weight produced 3.5M fake accounts.

Source: Wells Fargo, 2016

Delhi paid per dead cobra. Citizens bred cobras. When the bounty ended, breeders released them — population went up.

Real-time price → driver supply response → rider wait drops. Works because drivers see incentive in their own UI.

'75% of guests in this room reuse their towels' beats abstract environmental appeals by ~25%.

Source: Goldstein, Cialdini & Griskevicius (2008)

Opower-style 'you used 23% more than similar homes' reduces consumption ~2% on average and ~6% for top users.

Source: Allcott (2011)

A deliberately bad middle tier makes the premium tier feel obvious. The decoy is never meant to sell — it shifts the reference point.

Source: Ariely (Economist subscription study)

Default 18/22/25% buttons raise average tips ~12% versus blank entry. The middle option anchors the perceived norm.

Block advancement until 90% mastery. Replaces 'how far did you get' with 'how solid is what you have.'

Tiered stars with expiration creates Goal Gradient (close to free drink) + Loss Aversion (stars expire) every visit.

A 19-item checklist cut surgical deaths ~47%. Removes cognitive load and creates social permission to call out the surgeon.

Source: Gawande / Pronovost