Parameter: λ14 Identified

Algebraic Equations:

σ11λ1414

Single Door Criterion:

{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}
{1} ⊥ {3,4} | {2}
{1} ⊥ {4} | {2,3}

Parameter: λ23

Parameter: λ24 Identified

Algebraic Equations:

σ23λ2434,
σ22λ2424

Single Door Criterion:

{2} ⊥ {1,4} | {}
{2} ⊥ {1,4} | {3}
{2} ⊥ {4} | {1}
{2} ⊥ {4} | {1,3}

Instrumental Variable:

3 | {}
3 | {1}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω22 Identified

Algebraic Equations:

2222

Parameter: ω23

Parameter: ω33

Parameter: ω44 Identified

Algebraic Equations:

σ142σ2311σ24σ3411σ23σ4411σ23ω44,
σ142σ2211σ24211σ22σ4411σ22ω44

Vanishing Ideal


Constraint Set:

σ13,
σ12,
σ23σ2422σ34

All constraints are determinantal

Trek-separation:

{1} ⊥ {2,3} | ({},{})
{3,1} ⊥ {2,3} | ({3},{})
{4,1} ⊥ {2,3} | ({4},{})
{2,3} ⊥ {2,1,4} | ({},{2})
{1,2,3} ⊥ {2,1,4} | ({1},{2})
{4,2,3} ⊥ {2,1,4} | ({4},{2})
{1,2,3} ⊥ {1,2,4} | ({},{1,2})