Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2} | {}

Parameter: λ23

Parameter: λ24 Identified

Algebraic Equations:

σ232λ2422σ33λ2424σ3323σ34,
σ13σ23λ2412σ33λ2414σ3313σ34,
σ13σ22λ2412σ23λ2414σ2313σ24

Single Door Criterion:

{2} ⊥ {4} | {3}
{2} ⊥ {4} | {1,3}

Instrumental Variable:

1 | {3}

Parameter: λ34 Identified

Algebraic Equations:

σ232λ3423σ2422σ33λ3422σ34,
σ13σ23λ3414σ2312σ33λ3412σ34,
σ13σ22λ3414σ2212σ23λ3412σ24

Single Door Criterion:

{3} ⊥ {4} | {2}
{3} ⊥ {4} | {1,2}

Instrumental Variable:

1 | {2}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω13

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω23

Parameter: ω33

Parameter: ω44 Identified

Algebraic Equations:

242σ33+2σ23σ24σ3422σ342232σ4422σ33σ44232ω4422σ33ω44,
14σ24σ3314σ23σ3413σ24σ3412σ34213σ23σ4412σ33σ4413σ23ω4412σ33ω44,
14σ23σ2413σ24214σ22σ3412σ24σ3413σ22σ4412σ23σ4413σ22ω4412σ23ω44

Total Effect of X1 on X3: λ12λ23

Total Effect of X1 on X4: λ12λ23λ3412λ24

Path-specific Effect of X1 on X4: λ12λ23λ34

Path-specific Effect of X1 on X4: λ12λ24 Identified

Algebraic Equations:

σ11σ232λ12λ2411σ22σ33λ12λ2412σ24σ3312σ23σ34,
σ11σ13σ23λ12λ2411σ12σ33λ12λ2412σ14σ3312σ13σ34,
σ11σ13σ22λ12λ2411σ12σ23λ12λ2412σ14σ2312σ13σ24

Total Effect of X2 on X4: λ23λ3424

Path-specific Effect of X2 on X4: λ23λ34

Vanishing Ideal


Constraint Set:

σ14σ23213σ23σ2414σ22σ3312σ24σ3313σ22σ3412σ23σ34

All constraints are determinantal

Trek-separation:

{1,2,3} ⊥ {2,3,4} | ({},{2,3})