
Parameter: λ12 Identified
Algebraic Equations:
σ13λ12-σ23,
σ11λ12-σ12
Single Door Criterion:
{1} ⊥ {2} | {}
{1} ⊥ {2} | {3}
Instrumental Variable:
3 | {}
Parameter: λ14 Identified
Algebraic Equations:
σ132σ22λ14-σ11σ232λ14-σ14σ232+σ13σ23σ24-σ13σ22σ34+σ12σ23σ34,
σ11σ13σ22λ14-σ11σ12σ23λ14-σ12σ14σ23+σ11σ23σ24+σ122σ34-σ11σ22σ34,
σ11σ122σ23λ14+σ122σ14σ23-σ112σ22σ23λ14-σ11σ12σ23σ24-σ123σ34+σ11σ12σ22σ34
Parameter: λ24 Identified
Algebraic Equations:
σ13σ22λ24-σ12σ23λ24+σ14σ23-σ13σ24,
σ122λ24-σ12σ14-σ11σ22λ24+σ11σ24
Single Door Criterion:
{2} ⊥ {3,4} | {1}
{2} ⊥ {4} | {1,3}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω13 Identified
Algebraic Equations:
-σ13+ω13
Parameter: ω14 Identified
Algebraic Equations:
-σ14σ23+σ12σ34+σ23ω14,
-σ13σ14+σ11σ34+σ13ω14
Parameter: ω22 Identified
Algebraic Equations:
-σ13σ22+σ12σ23+σ13ω22,
σ122-σ11σ22+σ11ω22
Parameter: ω33 Identified
Algebraic Equations:
-σ33+ω33
Parameter: ω44 Identified
Algebraic Equations:
σ142σ232-2σ13σ14σ23σ24+σ132σ242+2σ13σ14σ22σ34-2σ12σ14σ23σ34+σ122σ342-σ11σ22σ342-σ132σ22σ44+σ11σ232σ44+σ132σ22ω44-σ11σ232ω44,
σ12σ142σ232-2σ11σ14σ232σ24+σ11σ13σ23σ242-2σ122σ14σ23σ34+2σ11σ14σ22σ23σ34+σ123σ342-σ11σ12σ22σ342-σ11σ13σ22σ23σ44+σ11σ12σ232σ44+σ11σ13σ22σ23ω44-σ11σ12σ232ω44,
-σ122σ142σ232+2σ11σ12σ14σ232σ24-σ112σ232σ242+2σ123σ14σ23σ34-2σ11σ12σ14σ22σ23σ34-σ124σ342+σ11σ122σ22σ342-σ11σ122σ232σ44+σ112σ22σ232σ44+σ11σ122σ232ω44-σ112σ22σ232ω44
Total Effect of X1 on X4: λ12λ24+λ14 Identified
Each Parameter Identified
Constraint Set:
σ12σ13-σ11σ23
All constraints are determinantal
Trek-separation:
{1,2} ⊥ {1,3} | ({1},{})
Algebraic Equations:
σ13λ12-σ23,
σ11λ12-σ12
Single Door Criterion:
{1} ⊥ {2} | {}
{1} ⊥ {2} | {3}
Instrumental Variable:
3 | {}
Parameter: λ14 Identified
Algebraic Equations:
σ132σ22λ14-σ11σ232λ14-σ14σ232+σ13σ23σ24-σ13σ22σ34+σ12σ23σ34,
σ11σ13σ22λ14-σ11σ12σ23λ14-σ12σ14σ23+σ11σ23σ24+σ122σ34-σ11σ22σ34,
σ11σ122σ23λ14+σ122σ14σ23-σ112σ22σ23λ14-σ11σ12σ23σ24-σ123σ34+σ11σ12σ22σ34
Parameter: λ24 Identified
Algebraic Equations:
σ13σ22λ24-σ12σ23λ24+σ14σ23-σ13σ24,
σ122λ24-σ12σ14-σ11σ22λ24+σ11σ24
Single Door Criterion:
{2} ⊥ {3,4} | {1}
{2} ⊥ {4} | {1,3}
Parameter: ω11 Identified
Algebraic Equations:
-σ11+ω11
Parameter: ω13 Identified
Algebraic Equations:
-σ13+ω13
Parameter: ω14 Identified
Algebraic Equations:
-σ14σ23+σ12σ34+σ23ω14,
-σ13σ14+σ11σ34+σ13ω14
Parameter: ω22 Identified
Algebraic Equations:
-σ13σ22+σ12σ23+σ13ω22,
σ122-σ11σ22+σ11ω22
Parameter: ω33 Identified
Algebraic Equations:
-σ33+ω33
Parameter: ω44 Identified
Algebraic Equations:
σ142σ232-2σ13σ14σ23σ24+σ132σ242+2σ13σ14σ22σ34-2σ12σ14σ23σ34+σ122σ342-σ11σ22σ342-σ132σ22σ44+σ11σ232σ44+σ132σ22ω44-σ11σ232ω44,
σ12σ142σ232-2σ11σ14σ232σ24+σ11σ13σ23σ242-2σ122σ14σ23σ34+2σ11σ14σ22σ23σ34+σ123σ342-σ11σ12σ22σ342-σ11σ13σ22σ23σ44+σ11σ12σ232σ44+σ11σ13σ22σ23ω44-σ11σ12σ232ω44,
-σ122σ142σ232+2σ11σ12σ14σ232σ24-σ112σ232σ242+2σ123σ14σ23σ34-2σ11σ12σ14σ22σ23σ34-σ124σ342+σ11σ122σ22σ342-σ11σ122σ232σ44+σ112σ22σ232σ44+σ11σ122σ232ω44-σ112σ22σ232ω44
Total Effect of X1 on X4: λ12λ24+λ14 Identified
Each Parameter Identified
Vanishing Ideal
Constraint Set:
σ12σ13-σ11σ23
All constraints are determinantal
Trek-separation:
{1,2} ⊥ {1,3} | ({1},{})