Parameter: λ12 Identified

Algebraic Equations:

σ14λ1224,
σ11λ1212

Single Door Criterion:

{1} ⊥ {2} | {}
{1} ⊥ {2} | {4}

Instrumental Variable:

4 | {}

Parameter: λ13

Parameter: λ14 Identified

Algebraic Equations:

σ12λ1424,
σ11λ1414

Single Door Criterion:

{1} ⊥ {4} | {}
{1} ⊥ {4} | {2}

Instrumental Variable:

2 | {}

Parameter: λ23

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω22 Identified

Algebraic Equations:

14σ2212σ2414ω22,
σ12211σ2211ω22

Parameter: ω23

Parameter: ω33

Parameter: ω34 Identified

Algebraic Equations:

σ13σ2412σ3412ω34,
σ13σ1411σ3411ω34

Parameter: ω44 Identified

Algebraic Equations:

σ14σ2412σ4412ω44,
σ14211σ4411ω44

Total Effect of X1 on X3: λ12λ2313 Identified

Algebraic Equations:

σ11λ12λ2311λ1313

Back Door Criterion:

{1} ⊥ {2,3,4} | {}

Path-specific Effect of X1 on X3: λ12λ23

Vanishing Ideal


Constraint Set:

σ12σ1411σ24

All constraints are determinantal

Trek-separation:

{1,2} ⊥ {1,4} | ({1},{})
{1,2} ⊥ {1,4} | ({},{1})