The Skill Regression Predictor uses a mathematical model inspired by Ebbinghaus’ Forgetting Curve, which describes the exponential decay of memory over time. The core idea is that the longer a skill goes unused, the more likely it is to degrade—especially if it was complex to begin with. The formula takes into account the number of days since the skill was last practiced and multiplies that with the skill's complexity, applying an exponential decay factor to simulate how memory fades. A base score of 10 represents full retention, and this value decays at a rate controlled by a small constant (decay rate), tuned for moderate skill loss over time. This approach provides an intuitive score between 0 and 10 that reflects current skill retention.

Score Range	Interpretation	Description
8 – 10	🟢 Fresh	Recently practiced and well retained. You’re ready for advanced concepts.
4 – 7	🟡 Rusty	Some memory loss. A quick review of intermediate topics is recommended.
1 – 3	🟠 Weak	Significant decay. Rebuild your base by revisiting beginner topics.
0 or less	🔴 Forgotten	The skill is likely forgotten. Restart from the basics.