Parameter: λ12

Parameter: λ14 Identified

Algebraic Equations:

σ12λ1424,
σ11λ1414

Single Door Criterion:

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

Instrumental Variable:

2 | {}

Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323,
σ12λ2313,
13σ1411σ24λ23

Single Door Criterion:

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

Instrumental Variable:

1 | {}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω12

Parameter: ω22

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33,
σ13σ2312σ3312ω33,
σ13σ14σ2311σ24σ3311σ24ω33

Parameter: ω34 Identified

Algebraic Equations:

σ23σ2422σ3422ω34,
σ13σ2412σ3412ω34,
σ13σ1411σ3411ω34

Parameter: ω44 Identified

Algebraic Equations:

σ14σ2412σ4412ω44,
σ14211σ4411ω44

Total Effect of X1 on X3: λ12λ23

Vanishing Ideal


Constraint Set:

σ13σ2212σ23,
σ12σ1411σ24

All constraints are determinantal

Trek-separation:

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