Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3} | {}

Parameter: λ14

Parameter: λ23 Identified

Algebraic Equations:

σ12λ2313

Instrumental Variable:

1 | {}

Parameter: λ24

Parameter: λ34

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω23 Identified

Algebraic Equations:

σ13σ2212σ2312ω23

Parameter: ω33 Identified

Algebraic Equations:

132σ22+2σ12σ13σ23122σ33122ω33

Parameter: ω34

Parameter: ω44

Total Effect of X1 on X3: λ12λ23 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3,4} | {}

Total Effect of X1 on X4: λ12λ23λ3412λ2414 Identified

Algebraic Equations:

σ11λ12λ23λ3411λ12λ2411λ1414

Back Door Criterion:

{1} ⊥ {2,3,4} | {}

Path-specific Effect of X1 on X4: λ12λ23λ34

Path-specific Effect of X1 on X4: λ12λ24

Total Effect of X2 on X4: λ23λ3424

Path-specific Effect of X2 on X4: λ23λ34

Vanishing Ideal

Zero Vanishing Ideal