Information Decay Modeling

Information decays at different rates depending on the domain. A company's headquarters location has a half-life of years. A company's headcount has a half-life of months. A company's pricing has a half-life of weeks in competitive markets. A company's market sentiment has a half-life of days after a major event. Decay modeling assigns a freshness score to information based on its age relative to its domain's rate of change. A six-month-old headcount figure is stale. A six-month-old founding date is fine. The model prevents your pipeline from treating fresh data and stale data with equal confidence.

## Information Decay Rate Reference

SLOW DECAY (half-life: 1-5 years)
- Company founding date, HQ location
- Executive backgrounds, board composition
- Patent portfolio, core technology stack
- Industry classification, regulatory status

MODERATE DECAY (half-life: 3-12 months)
- Headcount, org structure
- Revenue (annual), funding status
- Product feature set, platform architecture
- Partnership ecosystem

FAST DECAY (half-life: 1-12 weeks)
- Pricing, promotional offers
- Job postings, hiring velocity
- Competitive positioning language
- Market sentiment, analyst ratings

RAPID DECAY (half-life: 1-7 days)
- Stock price, trading volume
- Social media sentiment
- News cycle positioning
- Event-specific market reaction

Rule: Weight = base_credibility × freshness_score
freshness_score = 0.5 ^ (age / half_life)