Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3} | {}

Parameter: λ14

Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323,
σ12λ2313

Single Door Criterion:

{2} ⊥ {3} | {}
{2} ⊥ {3,4} | {1}

Instrumental Variable:

1 | {}

Parameter: λ34 Identified

Algebraic Equations:

σ12σ13λ3412σ1411σ23λ3411σ24,
12σ14σ22122σ23λ3411σ22σ23λ3411σ22σ24

Instrumental Variable:

2 | {1}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω14

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33,
σ13σ2312σ3312ω33

Parameter: ω34 Identified

Algebraic Equations:

13σ14σ23132σ2412σ14σ3311σ24σ3312σ13σ3411σ23σ3412σ13ω3411σ23ω34,
12σ14σ23212σ13σ23σ2412σ14σ22σ3311σ22σ24σ33122σ23σ3411σ22σ23σ34122σ23ω3411σ22σ23ω34

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: λ12λ23λ3414

Path-specific Effect of X1 on X4: λ12λ23λ34 Identified

Algebraic Equations:

σ11σ12σ13λ12λ23λ3412σ13σ14112σ23λ12λ23λ3411σ13σ24,
σ11σ122λ12λ23λ34122σ14112σ22λ12λ23λ3411σ12σ24

Total Effect of X2 on X4: λ23λ34 Identified

Each Parameter Identified

Back Door Criterion:


{2} ⊥ {3,4} | {1}

Vanishing Ideal


Constraint Set:

σ13σ2212σ23

All constraints are determinantal

Trek-separation:

{1,2} ⊥ {2,3} | ({},{2})