Parameter: λ14 Identified

Algebraic Equations:

σ13λ1434,
σ12λ1424

Instrumental Variable:

2 | {}
2 | {3}
3 | {}

Parameter: λ23 Identified

Algebraic Equations:

σ24λ2334,
σ22λ2323,
σ12λ2313

Single Door Criterion:

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

Instrumental Variable:

1 | {}
1 | {4}
4 | {}
4 | {1}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω12 Identified

Algebraic Equations:

1212

Parameter: ω14 Identified

Algebraic Equations:

13σ1411σ3413ω14,
12σ1411σ2412ω14

Parameter: ω22 Identified

Algebraic Equations:

2222

Parameter: ω33 Identified

Algebraic Equations:

24σ3323σ3424ω33,
σ23222σ3322ω33,
σ13σ2312σ3312ω33

Parameter: ω44 Identified

Algebraic Equations:

13σ14σ3411σ342132σ44132ω44,
12σ14σ3411σ24σ3412σ13σ4412σ13ω44,
12σ14σ2411σ242122σ44122ω44

Vanishing Ideal


Constraint Set:

σ23σ2422σ34,
σ13σ2412σ34,
σ13σ2212σ23

All constraints are determinantal

Trek-separation:

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