Reputation Cooperation Conditions
When designing or evaluating any reputation system - marketplaces, review platforms, professional networks, or internal trust systems.
Framework identifying the four conditions that must hold for reputation systems to create stable tit-for-tat cooperation, derived from both vampire bat biology and eBay's marketplace success.
When to Use Reputation Cooperation Conditions
When designing or evaluating any reputation system - marketplaces, review platforms, professional networks, or internal trust systems. Use to diagnose why reputation systems fail or succeed.
How to Apply
Make Future Interactions Valuable
Future value of maintaining good reputation must exceed present gain from cheating
Questions to Ask
- Would a user sacrifice years of reputation-building for one fraudulent transaction?
- Does the platform provide enough ongoing value to make return worthwhile?
Outputs
- Calculated ratio of future opportunity value to one-time cheating gain
Make Memory Public and Permanent
Reputation information must be easily accessible to all potential partners and cannot be erased
Questions to Ask
- Can potential partners easily access complete behavioral history?
- Can users delete or hide negative feedback?
Outputs
- Assessment of memory accessibility and permanence
Make Reputation Costly to Rebuild
Starting fresh must be harder than maintaining honesty - preventing cheaters from simply creating new identities
Questions to Ask
- How much time/investment required to build trusted reputation?
- What verification prevents easy account recreation?
Outputs
- Calculated cost of reputation rebuilding vs. honest behavior
Make Cheating Detection Likely
High probability that cheating gets detected and recorded, making reputational cost predictable
Questions to Ask
- What percentage of victims leave negative feedback?
- Can cheaters game detection systems?
Outputs
- Detection probability rate and gaming vulnerability assessment