Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3,4} | {}

Parameter: λ23 Identified

Algebraic Equations:

σ12λ2313

Instrumental Variable:

1 | {}

Parameter: λ24 Identified

Algebraic Equations:

σ12λ2414

Instrumental Variable:

1 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω23 Identified

Algebraic Equations:

σ13σ2212σ2312ω23

Parameter: ω24 Identified

Algebraic Equations:

σ14σ2212σ2412ω24

Parameter: ω33 Identified

Algebraic Equations:

132σ22+2σ12σ13σ23122σ33122ω33

Parameter: ω34 Identified

Algebraic Equations:

13σ14σ2212σ14σ2312σ13σ24122σ34122ω34

Parameter: ω44 Identified

Algebraic Equations:

142σ22+2σ12σ14σ24122σ44122ω44

Total Effect of X1 on X3: λ12λ23 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3,4} | {}

Total Effect of X1 on X4: λ12λ24 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3,4} | {}

Vanishing Ideal

Zero Vanishing Ideal