
Parameter: λ12 Identified
Algebraic Equations:
σ11λ12-σ12
Single Door Criterion:
{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}
Parameter: λ24 Identified
Algebraic Equations:
σ12λ24-σ14
Instrumental Variable:
1 | {}
1 | {3}
Parameter: λ34 Identified
Algebraic Equations:
σ14σ22+σ12σ23λ34-σ12σ24
Instrumental Variable:
1 | {2}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω22 Identified
Algebraic Equations:
σ122-σ11σ22+σ11ω22
Parameter: ω23 Identified
Algebraic Equations:
-σ23+ω23
Parameter: ω33 Identified
Algebraic Equations:
-σ33+ω33
Parameter: ω34 Identified
Algebraic Equations:
σ14σ232-σ14σ22σ33+σ12σ24σ33-σ12σ23σ34+σ12σ23ω34
Parameter: ω44 Identified
Algebraic Equations:
σ142σ22σ232-σ142σ222σ33+2σ12σ14σ22σ24σ33-σ122σ242σ33-2σ12σ14σ22σ23σ34+2σ122σ23σ24σ34-σ122σ232σ44+σ122σ232ω44
Total Effect of X1 on X4: λ12λ24 Identified
Each Parameter Identified
Back Door Criterion:
{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}
Constraint Set:
σ13
All constraints are determinantal
Trek-separation:
{1} ⊥ {3} | ({},{})
Algebraic Equations:
σ11λ12-σ12
Single Door Criterion:
{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}
Parameter: λ24 Identified
Algebraic Equations:
σ12λ24-σ14
Instrumental Variable:
1 | {}
1 | {3}
Parameter: λ34 Identified
Algebraic Equations:
σ14σ22+σ12σ23λ34-σ12σ24
Instrumental Variable:
1 | {2}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω22 Identified
Algebraic Equations:
σ122-σ11σ22+σ11ω22
Parameter: ω23 Identified
Algebraic Equations:
-σ23+ω23
Parameter: ω33 Identified
Algebraic Equations:
-σ33+ω33
Parameter: ω34 Identified
Algebraic Equations:
σ14σ232-σ14σ22σ33+σ12σ24σ33-σ12σ23σ34+σ12σ23ω34
Parameter: ω44 Identified
Algebraic Equations:
σ142σ22σ232-σ142σ222σ33+2σ12σ14σ22σ24σ33-σ122σ242σ33-2σ12σ14σ22σ23σ34+2σ122σ23σ24σ34-σ122σ232σ44+σ122σ232ω44
Total Effect of X1 on X4: λ12λ24 Identified
Each Parameter Identified
Back Door Criterion:
{1} ⊥ {2,3,4} | {}
{1} ⊥ {2,4} | {3}
Vanishing Ideal
Constraint Set:
σ13
All constraints are determinantal
Trek-separation:
{1} ⊥ {3} | ({},{})