Parameter: λ12 Identified

Algebraic Equations:

σ13λ1223,
σ11λ1212

Single Door Criterion:

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

Instrumental Variable:

3 | {}

Parameter: λ34 Identified

Algebraic Equations:

σ33λ3434,
σ13λ3414,
12σ1411σ23λ34

Single Door Criterion:

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

Instrumental Variable:

1 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω13 Identified

Algebraic Equations:

1313

Parameter: ω22 Identified

Algebraic Equations:

13σ2212σ2313ω22,
σ12211σ2211ω22

Parameter: ω24 Identified

Algebraic Equations:

24σ3323σ3433ω24,
σ14σ2313σ2413ω24,
σ12σ1411σ2411ω24

Parameter: ω33 Identified

Algebraic Equations:

3333

Parameter: ω44 Identified

Algebraic Equations:

σ34233σ4433ω44,
σ14σ3413σ4413ω44,
σ12σ14σ3411σ23σ4411σ23ω44

Vanishing Ideal


Constraint Set:

σ14σ3313σ34,
σ12σ1311σ23

All constraints are determinantal

Trek-separation:

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