Evaluating joint probabilities of potential outcomes and observed variables, and their linear combinations, is a fundamental challenge in causal inference. This paper addresses the bounding and identification of these probabilities in settings with discrete treatment and discrete ordinal outcome. We propose new families of monotonicity assumptions and formulate the bounding problem as a linear programming problem. We further introduce a new monotonicity assumption specifically to achieve identification. Finally, we present numerical experiments to validate our methods and demonstrate their application using real-world datasets.
Figures & tables
Research
Treatment Type
Outcome Type
MA
Objective
Identification
Pearl (1999) ; Tian and Pearl (2000)
Binary
Binary
P(Y0=1,Y1=0)=0
PoC
✓
Mueller and Pearl (2023)
Binary
Binary
0≤P(Y0=1,Y1=0)≤ϵ
PoC
Zhang et al. (2025)
Binary
Ordinal
Y0≤Y1
PN
Zhang et al. (2025)
Binary
Ordinal
0≤Y1−Y0≤1
PN
✓
Manski (1997)
Discrete
General
Y0≤Y1≤⋯≤YdX−1
ACE
This paper
Discrete
Ordinal
Assumptions 7 ∼ 11
λ(P)
Table 1: Summary of monotonicity assumptions (MAs) in causal inference. The symbol ( ✓ ) indicates that the objective quantity is identified under the MA. λ(P) represents an arbitrary linear combination of the joint POs/OVs probabilities.
Assumption
LB
UB
(A1)
0.000 [0.000,0.000]
0.261 [0.247,0.274]
(A2)
0.064 [0.042,0.089]
0.261 [0.247,0.274]
(A3)
0.000 [0.000,0.000]
0.064 [0.042,0.089]
(A4)
0.014 [0.000,0.039]
0.114 [0.092,0.139]
Assumption
Identification
(A5)
0.064 [0.042,0.089]
Table 2: The means and 95% CIs of the estimates of P(Y0=0,Y1=0,Y2≥1) . LB stands for “lower bound” and UB stands for “upper bound.”
Assumption
LB
UB
(B1)
0.203 [0.000,0.489]
0.997 [0.956,1.000]
(B2)
0.293 [0.000,0.561]
0.997 [0.956,1.000]
(B3)
0.203 [0.000,0.489]
0.575 [0.192,0.740]
(B4)
0.207 [0.000,0.489]
0.783 [0.531,1.000]
Assumption
Identification
(B5)
0.575 [0.192,0.740]
Table 3: The means and 95% CIs of the estimates of P(Y0≤1,Y1≤1,Y2≤1∣X=3,Y=2) under exogeneity.
Assumption
LB
UB
(B1)
0.044 [0.000,0.280]
1.000 [1.000,1.000]
(B2)
0.044 [0.000,0.280]
0.251 [0.013,0.612]
(B3)
0.044 [0.000,0.280]
1.000 [1.000,1.000]
(B4)
0.044 [0.000,0.280]
0.404 [0.165,0.665]
Assumption
Identification
(B5)
0.251 [0.013,0.612]
Table 4: The means and 95% CIs of the estimates of P(Y1≥1,Y2≥1,Y3≥1∣X=0,Y=0) under exogeneity.
Appendix figures & tables24 assets
Supplementary material from the paper’s appendix.
Appendix
X=0,Y=0
Y0=0
Y0=1
Y0=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y2=0
1/40
0
0
0
0
0
0
0
0
Y2=1
1/40
1/40
0
0
0
0
0
0
0
Y2=2
1/40
1/40
1/40
0
0
0
0
0
0
Appendix
Table 5: Setting of simulations for Assumptions (i)-(v) in Section E.1
X=0,Y=0
Y0=0
Y0=1
Y0=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y2=0
0.011
0.010
0.042
0
0
0
0
0
0
Y2=1
0.045
0.059
0.069
0
0
0
0
0
0
Y2=2
0.017
0.041
0.047
0
0
0
0
0
0
Appendix
Table 6: Settings of P(Y1,Y0,Y2,X,Y) for comparing bounds based on [ Li and Pearl, 2024 ] and LP solver. When x=y , we set P(Y0,Y1,Y2,X=x,Y=y)=0 .
X=0,Y=0
Y0=0
Y0=1
Y0=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y2=0
1/20
0
0
0
0
0
0
0
0
Y2=1
1/20
1/20
0
0
0
0
0
0
0
Y2=2
0
0
0
0
0
0
0
0
0
Appendix
Table 7: Setting of simulations for Assumption (vi) in Section E.1
Exp.
MAs
N=10
N=100
N=1000
N=10000
(i)
3
3
3
3
(ii)
3
3
3
3
(iii)
3
3
3
3
(iv)
3
4
3
3
Appendix
Table 8: Running time of solving maximization and minimization problem of P(Y0=0,Y1=0,Y2=1) for one time in milliseconds. Each entry is the mean over 100 repetitions.
Exp.
MAs
N=10
N=100
N=1000
N=10000
(i)
2
3
2
3
(ii)
3
3
3
3
(iii)
3
3
2
2
(iv)
3
2
2
2
Appendix
Table 9: Running time of solving maximization and minimization problem of E[Y1−Y0∣X=2,Y=2] for one time in milliseconds. Each entry is the mean over 100 repetitions.
MAs
Bounds (Exp.)
N=10
N=100
N=1000
N=10000
(i)
LB
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
(i)
UB
0.224 [0.100,0.452]
0.265 [0.200,0.340]
0.274 [0.245,0.304]
0.275 [0.268,0.284]
(ii)
LB
0.002 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
(ii)
UB
0.224 [0.100,0.452]
0.265 [0.200,0.340]
0.274 [0.245,0.304]
0.275 [0.268,0.284]
(iii)
LB
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
(iii)
UB
0.163 [0.000,0.400]
0.167 [0.105,0.235]
0.166 [0.144,0.186]
0.167 [0.161,0.175]
Appendix
Table 10: Results of the estimates of the bounds of P(Y0=0,Y1=0,Y2=1) . We report the means and 95% confidence intervals (CIs). The true value of P(Y0=0,Y1=0,Y2=1) is 0.092.
MAs
Bounds (Obs.)
N=10
N=100
N=1000
N=10000
(i)
LB
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
(i)
UB
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
(ii)
LB
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
(ii)
UB
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
(iii)
LB
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
-2.000 [-2.000,-2.000]
(iii)
UB
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
2.000 [2.000,2.000]
Appendix
Table 11: Results of the estimates of the bounds of E[Y1−Y0∣X=2,Y=2] . We report the means and 95% confidence intervals (CIs). The true value of E[Y1−Y0∣X=2,Y=2] is 0.667.
MAs
Bounds (Exp.)
N=10
N=100
N=1000
N=10000
(i)
LB
0.417 [0.047,0.952]
0.441 [0.325,0.570]
0.432 [0.393,0.472]
0.432 [0.422,0.443]
(i)
UB
2.003 [0.900,3.052]
2.176 [1.803,2.485]
2.189 [2.077,2.313]
2.197 [2.151,2.240]
(ii)
LB
0.417 [0.047,0.952]
0.441 [0.325,0.570]
0.432 [0.393,0.472]
0.432 [0.422,0.443]
(ii)
UB
0.629 [0.048,1.300]
0.764 [0.539,1.016]
0.745 [0.659,0.816]
0.747 [0.725,0.771]
(iii)
LB
0.417 [0.047,0.952]
0.441 [0.325,0.570]
0.432 [0.393,0.472]
0.432 [0.422,0.443]
(iii)
UB
2.003 [0.900,3.052]
2.176 [1.803,2.485]
2.189 [2.077,2.313]
2.197 [2.151,2.240]
Appendix
Table 12: Results of the estimates of the bounds of E[(Y1−Y0)2] . We report the means and 95% confidence intervals (CIs). The true value of E[(Y1−Y0)2] is 0.583.
Bounds (Both)
N=10
N=100
N=1000
N=10000
LB ( [ Li and Pearl, 2024 ] )
0.056 [0.000,0.300]
0.003 [0.000,0.025]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
UB ( [ Li and Pearl, 2024 ] )
0.426 [0.100,0.700]
0.501 [0.410,0.570]
0.517 [0.485,0.549]
0.514 [0.505,0.526]
LB
0.056 [0.000,0.300]
0.003 [0.000,0.025]
0.000 [0.000,0.000]
0.000 [0.000,0.000]
UB
0.389 [0.100,0.600]
0.414 [0.305,0.508]
0.426 [0.387,0.451]
0.426 [0.411,0.435]
Appendix
Table 13: The bound of P(Y0=0,Y1=1,Y2=2) based on Theorem 11 in [ Li and Pearl, 2024 ] and LP solver under the setting in Table 6 . The true value of P(Y0=0,Y1=1,Y2=2) is 0.214.
Data
L
LB
UB
Obs
(All)
0.000 [0.000, 0.000]
0.351 [0.326, 0.374]
Exp. & Both
0.00
0.000 [0.000, 0.000]
0.274 [0.250, 0.301]
Exp. & Both
0.70
0.000 [0.000, 0.000]
0.274 [0.250, 0.301]
Exp. & Both
0.75
0.000 [0.000, 0.000]
0.274 [0.250, 0.301]
Exp. & Both
0.80
0.000 [0.000, 0.000]
0.274 [0.250, 0.301]
Exp. & Both
0.85
0.000 [0.000, 0.000]
0.274 [0.250, 0.301]
Appendix
Table 14: Results of the estimates of the bounds of P(Y0=0,Y1=0,Y2=1) under assumption L≤P(Y0≤Y1≤Y2) and N=1000 . We report the means and 95% confidence intervals (CIs). The true value of P(Y0=0,Y1=0,Y2=1) is 0.092.
Figure 1: Results of the estimates of the bounds of P(Y0=0,Y1=0,Y2=1) as L varies. The x-axis shows the value of L , and the y-axis shows the mean estimates of the bounds of P(Y0=0,Y1=0,Y2=1) .
Data
L
LB
UB
Obs
(All)
-2.000 [-2.000, -2.000]
2.000 [2.000, 2.000]
Both
0.00
-1.509 [-1.850, -1.267]
2.000 [2.000, 2.000]
Both
0.70
-1.509 [-1.850, -1.267]
2.000 [2.000, 2.000]
Both
0.75
-1.509 [-1.850, -1.267]
2.000 [2.000, 2.000]
Both
0.80
-1.509 [-1.850, -1.267]
2.000 [2.000, 2.000]
Both
0.85
-1.509 [-1.850, -1.267]
2.000 [2.000, 2.000]
Appendix
Table 15: Results of the estimates of the bounds of E[Y1−Y0∣X=2,Y=2] under assumption L≤P(Y0≤Y1≤Y2) and N=1000 . We report the means and 95% confidence intervals (CIs). The true value of E[Y1−Y0∣X=2,Y=2] is 0.667.
Figure 2: Results of the estimates of the bounds of E[Y1−Y0∣X=2,Y=2] as L varies. The x-axis shows the value of L , and the y-axis shows the mean estimates of the bounds of E[Y1−Y0∣X=2,Y=2] .
Data
L
LB
UB
Exp.
0.00
0.435 [0.392, 0.474]
2.196 [2.073, 2.339]
Exp.
0.70
0.435 [0.392, 0.474]
2.195 [2.073, 2.331]
Exp.
0.75
0.435 [0.392, 0.474]
2.141 [2.003, 2.272]
Exp.
0.80
0.435 [0.392, 0.474]
2.041 [1.903, 2.172]
Exp.
0.85
0.435 [0.392, 0.474]
1.921 [1.803, 2.024]
Exp.
0.86
0.435 [0.392, 0.474]
1.863 [1.775, 1.952]
Appendix
Table 16: Results of the estimates of the bounds of E[(Y1−Y0)2] under assumption L≤P(Y0≤Y1≤Y2) and N=1000 . We report the means and 95% confidence intervals (CIs). The true value of E[(Y1−Y0)2] is 0.583.
Figure 3: Results of the estimates of the bounds of E[(Y1−Y0)2] as L varies. The x-axis shows the value of L , and the y-axis shows the mean estimates of the bounds of E[(Y1−Y0)2] .
L3=0.900
L2=0.900
L2=0.925
L2=0.950
L2=0.975
L2=1.000
L1=0.900
LB
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.001 [0.000, 0.008]
0.009 [0.000, 0.033]
0.033 [0.012, 0.058]
L1=0.900
UB
0.233 [0.212, 0.258]
0.208 [0.187, 0.233]
0.183 [0.162, 0.208]
0.158 [0.137, 0.183]
0.133 [0.112, 0.158]
L1=0.925
LB
0.000 [0.000, 0.000]
0.001 [0.000, 0.008]
0.009 [0.000, 0.033]
0.033 [0.012, 0.058]
0.058 [0.037, 0.083]
L1=0.925
UB
0.233 [0.212, 0.258]
0.208 [0.187, 0.233]
0.183 [0.162, 0.208]
0.158 [0.137, 0.183]
0.133 [0.112, 0.158]
L1=0.950
LB
0.001 [0.000, 0.008]
0.009 [0.000, 0.033]
0.033 [0.012, 0.058]
0.058 [0.037, 0.083]
0.083 [0.062, 0.108]
Appendix
Table 17: Results of the estimates of bounds of P(Y0=0,Y1=0,Y2=1) under Assumption (vi) and N=1000 with experimental data / with both experimental and observational data. The true value of P(Y0=0,Y1=0,Y2=1) is 0.133.
L3=0.900
L2=0.900
L2=0.925
L2=0.950
L2=0.975
L2=1.000
L1=0.900
LB
-1.929 [-2.000, -1.667]
-1.713 [-1.909, -1.458]
-1.464 [-1.606, -1.250]
-1.214 [-1.303, -1.042]
-0.965 [-1.000, -0.833]
L1=0.900
UB
1.965 [1.833, 2.000]
1.965 [1.833, 2.000]
1.965 [1.833, 2.000]
1.965 [1.833, 2.000]
1.965 [1.833, 2.000]
L1=0.925
LB
-1.498 [-1.819, -1.250]
-1.498 [-1.819, -1.250]
-1.248 [-1.516, -1.042]
-0.998 [-1.213, -0.833]
-0.749 [-0.909, -0.625]
L1=0.925
UB
1.749 [1.625, 1.909]
1.749 [1.625, 1.909]
1.749 [1.625, 1.909]
1.749 [1.625, 1.909]
1.749 [1.625, 1.909]
L1=0.950
LB
-0.998 [-1.213, -0.833]
-0.998 [-1.213, -0.833]
-0.998 [-1.213, -0.833]
-0.749 [-0.909, -0.625]
-0.499 [-0.606, -0.417]
Appendix
Table 18: Results of the estimates of bounds of E[Y1−Y0∣X=2,Y=2] under Assumption (vi) and N=1000 with observational data. The true value of E[Y1−Y0∣X=2,Y=2] is 0.333.
L3=0.900
L2=0.900
L2=0.925
L2=0.950
L2=0.975
L2=1.000
L1=0.900
LB
-1.758 [-2.000, -1.436]
-1.556 [-1.835, -1.241]
-1.307 [-1.546, -1.022]
-1.057 [-1.268, -0.795]
-0.808 [-1.000, -0.564]
L1=0.900
UB
1.926 [1.767, 2.000]
1.926 [1.767, 2.000]
1.926 [1.767, 2.000]
1.926 [1.767, 2.000]
1.917 [1.752, 2.000]
L1=0.925
LB
-1.475 [-1.769, -1.248]
-1.461 [-1.769, -1.198]
-1.216 [-1.467, -0.998]
-0.966 [-1.164, -0.788]
-0.716 [-0.862, -0.564]
L1=0.925
UB
1.744 [1.625, 1.909]
1.744 [1.625, 1.909]
1.744 [1.625, 1.909]
1.744 [1.625, 1.909]
1.727 [1.551, 1.909]
L1=0.950
LB
-0.998 [-1.213, -0.833]
-0.998 [-1.213, -0.833]
-0.998 [-1.213, -0.833]
-0.749 [-0.909, -0.625]
-0.499 [-0.606, -0.417]
Appendix
Table 19: Results of the estimates of bounds of E[Y1−Y0∣X=2,Y=2] under Assumption (vi) and N=1000 with both experimental and observational data. The true value of E[Y1−Y0∣X=2,Y=2] is 0.333.
L3=0.900
L2=0.900
L2=0.925
L2=0.950
L2=0.975
L2=1.000
L1=0.900
LB
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
L1=0.900
UB
0.869 [0.842, 0.898]
0.869 [0.842, 0.898]
0.869 [0.842, 0.898]
0.869 [0.842, 0.898]
0.869 [0.842, 0.898]
L1=0.925
LB
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
L1=0.925
UB
0.719 [0.692, 0.748]
0.719 [0.692, 0.748]
0.719 [0.692, 0.748]
0.719 [0.692, 0.748]
0.719 [0.692, 0.748]
L1=0.950
LB
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
0.269 [0.242, 0.298]
Appendix
Table 20: Results of the estimates of bounds of E[(Y1−Y0)2] under Assumption (vi) and N=1000 with experimental data / with both experimental and observational data. The true value of E[(Y1−Y0)2] is 0.267.
L3=0.900
L2=0.900
L2=0.925
L2=0.950
L2=0.975
L2=1.000
L1=0.900
LB
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
L1=0.900
UB
1.200 [1.175, 1.219]
1.200 [1.175, 1.219]
1.197 [1.172, 1.218]
1.175 [1.149, 1.198]
1.150 [1.124, 1.173]
L1=0.925
LB
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
L1=0.925
UB
1.100 [1.075, 1.119]
1.100 [1.075, 1.119]
1.097 [1.072, 1.118]
1.075 [1.049, 1.098]
1.050 [1.024, 1.073]
L1=0.950
LB
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
0.000 [0.000, 0.000]
Appendix
Table 21: Results of the estimates of bounds of E[(Y1−Y0)2] under Assumption (vi) and N=1000 with observational data. The true value of E[(Y1−Y0)2] is 0.267.
X=0,Y=0
Y0=0
Y0=1
Y0=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y1=0
Y1=1
Y1=2
Y2=0
1/21
0
0
0
0
0
0
0
0
Y2=1
1/21
1/21
0
0
0
0
0
0
0
Y2=2
0
0
0
0
0
0
0
0
0
Appendix
Table 22: Setting of Simulations
MAs
Data
N=10
N=100
N=1000
N=10000
(I)
Exp.
0.142 [0.000,0.353]
0.145 [0.085,0.225]
0.142 [0.120,0.166]
0.143 [0.135,0.150]
(II)
Obs.
0.190 [0.000,0.500]
0.143 [0.020,0.309]
0.152 [0.085,0.226]
0.144 [0.128,0.157]
Appendix
Table 23: Results of the estimates of P(Y0=0,Y1=0,Y2=1) under identification assumptions. We report the means and 95% confidence intervals (CIs). The ground truth of P(Y0=0,Y1=0,Y2=1) is 0.143.
MAs
Data
N=10
N=100
N=1000
N=10000
(II)
Obs.
0.431 [0.000,1.000]
0.332 [0.042,0.700]
0.321 [0.202,0.465]
0.334 [0.288,0.382]
Appendix
Table 24: Results of the estimates of E[Y1−Y0∣X=2,Y=2] under identification assumptions. We report the means and 95% confidence intervals (CIs). The ground truth of E[Y1−Y0∣X=2,Y=2] is 0.333.
MAs
Data
N=10
N=100
N=1000
N=10000
(I)
Exp.
0.313 [0.000,0.600]
0.279 [0.200,0.350]
0.288 [0.264,0.314]
0.285 [0.278,0.294]
(II)
Obs.
0.395 [0.000,1.000]
0.303 [0.077,0.561]
0.285 [0.169,0.388]
0.282 [0.238,0.319]
Appendix
Table 25: Results of the estimates of E[(Y1−Y0)2] under identification assumptions. We report the means and 95% confidence intervals (CIs). The ground truth of E[(Y1−Y0)2] is 0.286.
Probabilities of causation are fundamental to individual-level explanation and decision making, yet they are inherently counterfactual and not point-identifiable from data in general. Existing bounds either disregard available covariates, require complete causal graphs, or rely on restrictive binary settings, limiting their practical use. In real-world applications, causal information is often partial but nontrivial. This paper proposes a general framework for bounding probabilities of causation using partial causal information. We show how the available structural or statistical information can be systematically incorporated as constraints in a optimization programming formulation, yielding tighter and formally valid bounds without full identifiability. This approach extends the applicability of probabilities of causation to realistic settings where causal knowledge is incomplete but informative.
Yuxuan Xie, Ang Li
University of Ottawa, Ontario, Canada · Department of Computer Science, Florida State University, FL, U.S.A.
Non-parametric (partial) identification of counterfactual queries typically relies on a fully specified causal graph. Motivated by settings with incomplete domain knowledge, we challenge this requirement by leveraging structural assumptions that are inherently implied by the query itself. We show that any counterfactual inquiry induces a, mostly partial, topological ordering over relevant variables, which, in turn, enables an explicit query parametrisation reducing the identification task to a linear program. This allows bounding arbitrary counterfactual and nested counterfactual queries. Our work can be viewed as a generalisation of the classical bounding framework of Tian and Pearl (2000), originally developed for probabilities of causation. We also prove the tightness of our bounds by constructing structural causal models that attain the bounds whilst being compatible with both the observed data and the query-implied order. To assess both the generality and practical utility of the proposed bounding procedure, we revisit several case studies from the literature, demonstrating how the derived bounds can be used to yield informative insights even in the absence of an input causal graph.
Eric Rossetto, Alessandro Antonucci
Istituto Dalle Molle di Studi sull’Intelligenza Artificiale (IDSIA) Scuola Universitaria Professionale della Svizzera Italiana (SUPSI) Lugano, Switzerland
Probabilities of causation (PoCs) characterize individual causal responses that cannot be directly observed and therefore generally require partial identification. Tian and Pearl first derived theoretically sharp bounds for binary PoCs, including the probability of necessity (PN), the probability of sufficiency (PS), and the probability of necessity and sufficiency (PNS). Mueller et al. subsequently tightened the bounds for binary PNS by incorporating causal information encoded in covariates and mediators. More recently, Li and Pearl, as well as Shu et al., extended PoCs to multivalued settings and derived corresponding theoretical bounds. These developments naturally raise the question of whether additional causal knowledge can further tighten the bounds in multivalued settings. This paper addresses this question by deriving tighter bounds for multivalued PoCs through the incorporation of causal information encoded in covariates and mediators. We illustrate the theoretical results with toy examples, while simulation studies further demonstrate that the proposed bounds are tighter than existing nonbinary bounds.
Xin Shu, Zhen Lei, Ang Li
Department of Computer Science, Florida State University