Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3} | {}
{1} ⊥ {2} | {3}

Parameter: λ14 Identified

Algebraic Equations:

σ11σ23λ1414σ2312σ34

Parameter: λ24 Identified

Algebraic Equations:

σ23λ2434

Instrumental Variable:

3 | {}
3 | {1}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω23 Identified

Algebraic Equations:

2323

Parameter: ω24 Identified

Algebraic Equations:

σ12σ14σ2311σ23σ24122σ3411σ22σ3411σ23ω24

Parameter: ω33 Identified

Algebraic Equations:

3333

Parameter: ω44 Identified

Algebraic Equations:

σ142σ232-2σ12σ14σ23σ34+2σ11σ23σ24σ34122σ34211σ22σ34211σ232σ4411σ232ω44

Total Effect of X1 on X4: λ12λ2414 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}

Vanishing Ideal


Constraint Set:

σ13

All constraints are determinantal

Trek-separation:

{1} ⊥ {3} | ({},{})