Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323

Single Door Criterion:

{2} ⊥ {3,4} | {}

Parameter: λ34 Identified

Algebraic Equations:

σ23λ3424

Instrumental Variable:

2 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω12 Identified

Algebraic Equations:

1212

Parameter: ω13 Identified

Algebraic Equations:

13σ2212σ2322ω13

Parameter: ω14 Identified

Algebraic Equations:

14σ2313σ2423ω14

Parameter: ω22 Identified

Algebraic Equations:

2222

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33

Parameter: ω34 Identified

Algebraic Equations:

σ24σ3323σ3423ω34

Parameter: ω44 Identified

Algebraic Equations:

242σ33+2σ23σ24σ34232σ44232ω44

Total Effect of X2 on X4: λ23λ34 Identified

Each Parameter Identified

Back Door Criterion:


{2} ⊥ {3,4} | {}

Vanishing Ideal

Zero Vanishing Ideal