Mental Model
Every primitive in Book Duplex belongs to one of three buckets:
- Position
- Structure
- Flow
Everything else is a transformation or interaction of those three.
Position
Position answers where the pair is relative to equilibrium.
- Ratio Price tells you the relative valuation.
- Displacement tells you how stretched that valuation is.
Position is the state of price. It does not explain whether the move is allowed to continue.
Structure
Structure answers what liquidity permits.
Structure is the terrain. It defines friction, support, resistance, and how that terrain is changing through time.
Flow
Flow answers what participants are actually doing.
Flow is commitment. It is the capital that either confirms or fails to confirm the structural picture.
The Core Compression
The whole system can be reduced to:
pressure + friction + participation
- pressure: directional structural and flow bias
- friction: how hard the book makes movement
- participation: whether real traders are funding the move
How Edge Appears
Edge does not come from a single metric. It comes from either:
- alignment
- conflict
Alignment means the system agrees. Conflict means one layer is lying, lagging, or being overrun.
Canonical Interaction Examples
Displacement + Depth
- stretched + thin liquidity ahead -> continuation
- stretched + thick opposing liquidity -> rejection
Log(A/B) + Centroid
- positive near-mid imbalance -> immediate structural support
- positive imbalance far away -> latent support, not immediate support
Trade Profile + Depth
- aggressive buying into thick supply -> absorption
- aggressive buying into thin supply -> expansion
Flow vs Structure
- agreement -> stable moves
- conflict -> traps, adverse selection, or reversals
Full-System Read
The highest-quality continuation read looks like:
displacement positive
+ Log(A/B) positive near mid
+ centroid positive
+ trade flow positive
+ SLS gravity rising
-> continuation probability increases
The inverse uses the same logic in reverse.
Next Steps
- Study the individual Primitives
- Then move into Tutorials
- Keep Chart Panels open while reading