Models From First Principles 02: EBT — From One Score to Q, V, Policy and Advantage

Sat, 08 Aug 2026 14:39:00 +0100

EBT — From One Score to Q, V, Policy and Advantage

In the previous post we built MR.Q: a small model that takes a context embedding and a response embedding, combines them, and predicts one scalar.

That architecture is useful because it is brutally simple:

context embedding
        +
response embedding
        ↓
     encoder
        ↓
   representation z
        ↓
    predictor
        ↓
      Q value

But one scalar eventually becomes restrictive.