Parameter: λ12 Identified

Algebraic Equations:

σ14λ1224

Instrumental Variable:

4 | {}

Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323,
σ12λ2313

Single Door Criterion:

{2} ⊥ {3} | {}
{2} ⊥ {3} | {1}

Instrumental Variable:

1 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω12 Identified

Algebraic Equations:

12σ1411σ2414ω12

Parameter: ω14 Identified

Algebraic Equations:

1414

Parameter: ω22 Identified

Algebraic Equations:

142σ22+2σ12σ14σ2411σ242142ω22

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33,
σ13σ2312σ3312ω33

Parameter: ω34 Identified

Algebraic Equations:

σ23σ2422σ3422ω34,
σ13σ2412σ3412ω34

Parameter: ω44 Identified

Algebraic Equations:

4444

Total Effect of X1 on X3: λ12λ23 Identified

Each Parameter Identified

Vanishing Ideal


Constraint Set:

σ13σ2212σ23

All constraints are determinantal

Trek-separation:

{1,2} ⊥ {2,3} | ({},{2})