
Parameter: λ12 Identified
Algebraic Equations:
σ14λ12-σ24,
-σ23σ24+σ12σ34λ12,
-σ13σ24+σ11σ34λ12
Instrumental Variable:
4 | {}
Parameter: λ13 Identified
Algebraic Equations:
σ14λ13-σ34,
σ12λ13-σ23,
σ11λ13-σ13
Single Door Criterion:
{1} ⊥ {3} | {}
{1} ⊥ {3} | {4}
{1} ⊥ {3} | {2}
{1} ⊥ {3} | {2,4}
Instrumental Variable:
2 | {}
2 | {4}
4 | {}
4 | {2}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω12 Identified
Algebraic Equations:
σ13σ24-σ12σ34+σ34ω12,
-σ12σ14+σ11σ24+σ14ω12
Parameter: ω14 Identified
Algebraic Equations:
-σ14+ω14
Parameter: ω22 Identified
Algebraic Equations:
-σ13σ242-σ14σ22σ34+2σ12σ24σ34+σ14σ34ω22,
-σ142σ22+2σ12σ14σ24-σ11σ242+σ142ω22,
-σ13σ23σ242+2σ12σ23σ24σ34-σ12σ22σ342+σ12σ342ω22,
-σ132σ242+2σ11σ23σ24σ34-σ11σ22σ342+σ11σ342ω22
Parameter: ω33 Identified
Algebraic Equations:
-σ14σ33+σ13σ34+σ14ω33,
σ13σ23-σ12σ33+σ12ω33,
σ132-σ11σ33+σ11ω33
Parameter: ω44 Identified
Algebraic Equations:
-σ44+ω44
Constraint Set:
σ14σ23-σ12σ34,
σ13σ14-σ11σ34,
σ12σ13-σ11σ23
All constraints are determinantal
Trek-separation:
{1,3} ⊥ {1,2,4} | ({1},{})
{1,2,3} ⊥ {1,2,4} | ({1,2},{})
{1,4,3} ⊥ {1,2,4} | ({1,4},{})
Algebraic Equations:
σ14λ12-σ24,
-σ23σ24+σ12σ34λ12,
-σ13σ24+σ11σ34λ12
Instrumental Variable:
4 | {}
Parameter: λ13 Identified
Algebraic Equations:
σ14λ13-σ34,
σ12λ13-σ23,
σ11λ13-σ13
Single Door Criterion:
{1} ⊥ {3} | {}
{1} ⊥ {3} | {4}
{1} ⊥ {3} | {2}
{1} ⊥ {3} | {2,4}
Instrumental Variable:
2 | {}
2 | {4}
4 | {}
4 | {2}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω12 Identified
Algebraic Equations:
σ13σ24-σ12σ34+σ34ω12,
-σ12σ14+σ11σ24+σ14ω12
Parameter: ω14 Identified
Algebraic Equations:
-σ14+ω14
Parameter: ω22 Identified
Algebraic Equations:
-σ13σ242-σ14σ22σ34+2σ12σ24σ34+σ14σ34ω22,
-σ142σ22+2σ12σ14σ24-σ11σ242+σ142ω22,
-σ13σ23σ242+2σ12σ23σ24σ34-σ12σ22σ342+σ12σ342ω22,
-σ132σ242+2σ11σ23σ24σ34-σ11σ22σ342+σ11σ342ω22
Parameter: ω33 Identified
Algebraic Equations:
-σ14σ33+σ13σ34+σ14ω33,
σ13σ23-σ12σ33+σ12ω33,
σ132-σ11σ33+σ11ω33
Parameter: ω44 Identified
Algebraic Equations:
-σ44+ω44
Vanishing Ideal
Constraint Set:
σ14σ23-σ12σ34,
σ13σ14-σ11σ34,
σ12σ13-σ11σ23
All constraints are determinantal
Trek-separation:
{1,3} ⊥ {1,2,4} | ({1},{})
{1,2,3} ⊥ {1,2,4} | ({1,2},{})
{1,4,3} ⊥ {1,2,4} | ({1,4},{})