Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3} | {}

Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323,
σ12λ2313

Single Door Criterion:

{2} ⊥ {3} | {}
{2} ⊥ {3} | {1}

Instrumental Variable:

1 | {}

Parameter: λ24

Parameter: λ34

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω14 Identified

Algebraic Equations:

σ11σ14σ2311σ13σ2412σ13ω1411σ23ω14,
σ11σ14σ2211σ12σ24122ω1411σ22ω14

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33,
σ13σ2312σ3312ω33

Parameter: ω34

Parameter: ω44

Total Effect of X1 on X3: λ12λ23 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3} | {}

Total Effect of X1 on X4: λ12λ23λ3412λ24 Identified

Algebraic Equations:

σ11σ12σ13λ12λ23λ3411σ12σ13λ12λ2412σ13σ14112σ23λ12λ23λ34112σ23λ12λ2411σ13σ24,
σ11σ122λ12λ23λ3411σ122λ12λ24122σ14112σ22λ12λ23λ34112σ22λ12λ2411σ12σ24

Path-specific Effect of X1 on X4: λ12λ23λ34

Path-specific Effect of X1 on X4: λ12λ24

Total Effect of X2 on X4: λ23λ3424 Identified

Algebraic Equations:

σ122λ23λ34122λ2412σ1411σ22λ23λ3411σ22λ2411σ24

Back Door Criterion:

{2} ⊥ {3,4} | {1}

Path-specific Effect of X2 on X4: λ23λ34

Vanishing Ideal


Constraint Set:

σ13σ2212σ23

All constraints are determinantal

Trek-separation:

{1,2} ⊥ {2,3} | ({},{2})