Parameter: λ12 Identified

Algebraic Equations:

σ11λ1212

Single Door Criterion:

{1} ⊥ {2,3} | {}

Parameter: λ23 Identified

Algebraic Equations:

σ22λ2323,
σ12λ2313

Single Door Criterion:

{2} ⊥ {3} | {}
{2} ⊥ {3} | {1}

Instrumental Variable:

1 | {}

Parameter: λ24 Identified

Algebraic Equations:

σ12σ13σ23λ2413σ14σ2311σ232λ24132σ24122σ33λ2412σ14σ3311σ22σ33λ2411σ24σ3312σ13σ3411σ23σ34,
σ122σ232λ2412σ14σ23211σ22σ232λ2412σ13σ23σ24122σ22σ33λ2412σ14σ22σ3311σ222σ33λ2411σ22σ24σ33122σ23σ3411σ22σ23σ34

Single Door Criterion:

{2} ⊥ {4} | {1,3}

Parameter: λ34 Identified

Algebraic Equations:

σ232λ3423σ2422σ33λ3422σ34,
σ13σ23λ3413σ2412σ33λ3412σ34

Single Door Criterion:

{3} ⊥ {1,4} | {2}
{3} ⊥ {4} | {1,2}

Parameter: ω11 Identified

Algebraic Equations:

1111

Parameter: ω14 Identified

Algebraic Equations:

σ11σ14σ2311σ13σ2412σ13ω1411σ23ω14,
σ11σ14σ2211σ12σ24122ω1411σ22ω14

Parameter: ω22 Identified

Algebraic Equations:

σ12211σ2211ω22

Parameter: ω33 Identified

Algebraic Equations:

σ23222σ3322ω33,
σ13σ2312σ3312ω33

Parameter: ω44 Identified

Algebraic Equations:

12σ13σ142σ232+2σ12σ132σ14σ23σ2412σ133σ242122σ142σ23σ33-2σ122σ13σ14σ24σ33+2σ11σ12σ13σ242σ33112σ23σ242σ33+2σ122σ132σ24σ34-4σ11σ12σ13σ23σ24σ34+2σ112σ232σ24σ34123σ13σ342+2σ11σ122σ23σ342112σ22σ23σ342122σ132σ23σ44+2σ11σ12σ13σ232σ44112σ233σ44123σ13σ33σ44-2σ11σ122σ23σ33σ44112σ22σ23σ33σ44122σ132σ23ω44-2σ11σ12σ13σ232ω44112σ233ω44123σ13σ33ω44+2σ11σ122σ23σ33ω44112σ22σ23σ33ω44,
122σ142σ232+2σ122σ13σ14σ23σ24122σ132σ242122σ142σ22σ33-2σ123σ14σ24σ33+2σ11σ122σ242σ33112σ22σ242σ33+2σ123σ13σ24σ34-4σ11σ122σ23σ24σ34+2σ112σ22σ23σ24σ34124σ342+2σ11σ122σ22σ342112σ222σ342123σ13σ23σ44+2σ11σ122σ232σ44112σ22σ232σ44124σ33σ44-2σ11σ122σ22σ33σ44112σ222σ33σ44123σ13σ23ω44-2σ11σ122σ232ω44112σ22σ232ω44124σ33ω44+2σ11σ122σ22σ33ω44112σ222σ33ω44,
122σ142σ22σ232+2σ123σ14σ232σ24123σ13σ23σ242122σ142σ222σ33-2σ123σ14σ22σ24σ33+2σ11σ122σ22σ242σ33112σ222σ242σ33+2σ124σ23σ24σ34-4σ11σ122σ22σ23σ24σ34+2σ112σ222σ23σ24σ34124σ22σ342+2σ11σ122σ222σ342112σ223σ342124σ232σ44+2σ11σ122σ22σ232σ44112σ222σ232σ44124σ22σ33σ44-2σ11σ122σ222σ33σ44112σ223σ33σ44124σ232ω44-2σ11σ122σ22σ232ω44112σ222σ232ω44124σ22σ33ω44+2σ11σ122σ222σ33ω44112σ223σ33ω44

Total Effect of X1 on X3: λ12λ23 Identified

Each Parameter Identified

Back Door Criterion:


{1} ⊥ {2,3} | {}

Total Effect of X1 on X4: λ12λ23λ3412λ24 Identified

Each Parameter Identified

Total Effect of X2 on X4: λ23λ3424 Identified

Each Parameter Identified

Back Door Criterion:


{2} ⊥ {3,4} | {1}

Vanishing Ideal


Constraint Set:

σ13σ2212σ23

All constraints are determinantal

Trek-separation:

{1,2} ⊥ {2,3} | ({},{2})