Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2} | {}

Parameter: λ13 Identified

Algebraic Equations:

σ11λ1313

Single Door Criterion:

{1} ⊥ {3} | {}

Parameter: λ34 Identified

Algebraic Equations:

σ12σ13λ3412σ1411σ23λ3411σ24

Instrumental Variable:

2 | {1}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω14 Identified

Algebraic Equations:

σ11σ14σ2311σ13σ2412σ13ω1411σ23ω14

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω23 Identified

Algebraic Equations:

σ12σ1311σ2311ω23

Parameter: ω33 Identified

Algebraic Equations:

σ13211σ3311ω33

Parameter: ω34 Identified

Algebraic Equations:

13σ14σ23132σ2412σ14σ3311σ24σ3312σ13σ3411σ23σ3412σ13ω3411σ23ω34

Parameter: ω44 Identified

Algebraic Equations:

122σ142σ33+2σ11σ12σ14σ24σ33112σ242σ33+2σ122σ13σ14σ34-2σ11σ12σ14σ23σ34-2σ11σ12σ13σ24σ34+2σ112σ23σ24σ34122σ132σ44+2σ11σ12σ13σ23σ44112σ232σ44122σ132ω44-2σ11σ12σ13σ23ω44112σ232ω44

Total Effect of X1 on X4: λ13λ34 Identified

Each Parameter Identified

Vanishing Ideal

Zero Vanishing Ideal