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The Incentives Lab
HBT-COG-0561 · Dimension COG · Cognition

Ratio Bias

We judge probability by absolute counts rather than ratios.

Probability·Mental Model·Grade B·draft· enriching…

Scientific Definition

We judge probability by absolute counts rather than ratios.

Plain-English Definition

We judge probability by absolute counts rather than ratios.

Feynman Explanation

1 in 10 feels safer than 9 in 100. It isn't.

Core Principle

We judge probability by absolute counts rather than ratios.

Mechanisms

Psychological

Pending editorial review.

Behavioral Economic

We judge probability by absolute counts rather than ratios.

Neurological

Pending editorial review.

Evolutionary

Pending editorial review.

Sociological

Pending editorial review.

Computational

Pending editorial review.

Systems

Pricing, risk communication, and dashboards mislead via raw counts.

Inputs (Triggers)

Pending editorial review.

Outputs (Behaviors)

Pending editorial review.

Behavioral Signature

1 in 10 feels safer than 9 in 100. It isn't.

Examples

Everyday
  • People prefer drawing from a jar with 9 winners in 100 over one with 1 in 10.
Modern (Organizational)
  • Pricing, risk communication, and dashboards mislead via raw counts.
Historical

Pending editorial review.

Famous Experiments

Pending editorial review.

Design Principles

  • Always present both the ratio and the denominator. Force the comparison.

Measurement Approaches

Pending editorial review.

Evidence

Evidence Grade
B (A strongest → E speculative)
Replication
★★★☆☆
Intervention Confidence
3 / 5
Consensus
Pending editorial review (HBT v1.0 auto-seed).
Limitations
Pending editorial review (HBT v1.0 auto-seed).
Open Research Questions

Pending editorial review.

Primary References

Pending editorial review.

Signature Section

The Perverse Incentive Lens™

How this behavior is exploited — and how to redesign around it.

Exploitation
Pricing, risk communication, and dashboards mislead via raw counts.
Amplifying Incentives
Pricing, risk communication, and dashboards mislead via raw counts.
Org Failure Modes
Pricing, risk communication, and dashboards mislead via raw counts.
Societal Failure Modes
Pending editorial review (HBT v1.0 auto-seed).
Ethical Considerations
Pending editorial review (HBT v1.0 auto-seed).
Redesign Strategies
Always present both the ratio and the denominator. Force the comparison.
Diagnostic Questions
  • Always present both the ratio and the denominator. Force the comparison.
Warning Signs

Pending editorial review.

Red Flags

Pending editorial review.

Intervention Playbook
Individual
Always present both the ratio and the denominator. Force the comparison.
Team
Pending editorial review (HBT v1.0 auto-seed).
Organization
Pending editorial review (HBT v1.0 auto-seed).
Policy
Pending editorial review (HBT v1.0 auto-seed).
AI Implications
Detection
Pending editorial review (HBT v1.0 auto-seed).
Measurement
Pending editorial review (HBT v1.0 auto-seed).
Mitigation
Pending editorial review (HBT v1.0 auto-seed).
Responsible Use
Pending editorial review (HBT v1.0 auto-seed).

Interactive Mini Network

Click any neighbor to re-center the graph and follow the threads of connection.

HBT-COG-0561 · COG
Ratio Bias
RBBRBase Rate FallacyBRBayes' Rule (Updating)BTBayes' TheoremBUBayesian UpdatingBLBeginner's LuckBSBlack SwanCoCoincidenceDiDistributionsErErgodicityFEFermi Estimate

Knowledge Graph Neighbors

Version History

v1.1.0 · 2026-06-28Initial auto-seed from corpus.