Parameter: λ₁₄ Identified

Algebraic Equations:

σ₁₂λ₁₄-σ₂₄,
σ₁₁λ₁₄-σ₁₄

Single Door Criterion:

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

Instrumental Variable:

2 | {}
2 | {3}

Parameter: ω₁₁ Identified

Algebraic Equations:

-σ₁₁+ω₁₁

Parameter: ω₁₂ Identified

Algebraic Equations:

-σ₁₂+ω₁₂

Parameter: ω₂₂ Identified

Algebraic Equations:

-σ₂₂+ω₂₂

Parameter: ω₃₃ Identified

Algebraic Equations:

-σ₃₃+ω₃₃

Parameter: ω₄₄ Identified

Algebraic Equations:

σ₁₄σ₂₄-σ₁₂σ₄₄+σ₁₂ω₄₄,
σ₁₄²-σ₁₁σ₄₄+σ₁₁ω₄₄

Vanishing Ideal

Constraint Set:

σ₃₄,
σ₂₃,
σ₁₃,
σ₁₂σ₁₄-σ₁₁σ₂₄

All constraints are determinantal

Trek-separation:

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