Skill Decay Modeler (Ebbinghaus Personalized)
Ebbinghaus Forgetting Curve + individual adjustment: Predict EXACTLY when child will drop from 80% → 50% retention
Formula: R(t) = e^(-t/S) where R = retention, t = days, S = decay rate constant
📅 Recommended Schedule:
Review every 14 days
⏱️ Trigger review when retention drops to ~80%
📅 Recommended Schedule:
Review every 5 days
⏱️ Trigger review when retention drops to ~80%
📅 Recommended Schedule:
Review every 8-9 days
⏱️ Trigger review when retention drops to ~80%
Skill Complexity
Complex skills decay faster (higher β)
💡 Multi-step task: faster decay than single skill
Interest Level
High interest → slower decay
💡 Favorite game skill: 2-3x longer retention
Executive Function Level
Low EF → faster decay (working memory limitation)
💡 ADHD child: decay ~2x faster
Practice Spacing Quality
Distributed > massed practice
💡 5 spreads = 2x longer retention vs daily bunches
Sleep Quality
Poor sleep → significantly faster decay
💡 Sleep deprivation: ~2x decay rate increase
Identify individual decay rate from 3-5 practice sessions
Plot retention vs days; fit curve
Calculate days-to-50% threshold
Use formula; trigger review before that day
Schedule reviews at 80% retention point (sweet spot)
Not too early (wasted review) or too late (forgotten)
Re-calibrate decay rate every 2 weeks
Child improves; decay rate might change
