Optimal Correction Sets for Provable Redress of Contestable Causal Discovery
Organizations: Imperial College London, London, United Kingdom · University of Calabria, Rende, Italy
Abstract
Constraint-based causal discovery relies on conditional-independence (CI) tests that may conflict in finite samples, leaving no causal graph that satisfies them all. Causal Assumption-based Argumentation (ABA) makes these tests explicit as defeasible commitments, and offers correspondence guarantees with a subset of them, but its existing repair procedure releases facts heuristically and offers no formal response to a user's contestation of a release. We argue that contestable causal discovery requires an inspectable repair object, a justification for it, and a predictable revision procedure for such contestations. We therefore formulate CI-fact repair as a minimum-cost correction problem and implement it in Answer Set Programming (ASP). Building on Causal ABA, we provide a compact and efficient ASP encoding of causal consistency, with soundness and completeness guarantees, and a two-way projection correspondence between optimal stable models and minimum-cost correction sets. These results establish fidelity to retained facts, subset-minimality and cost optimality of the repair, conflict-based justifications for released facts, and formally guaranteed redress under user contestations. An empirical evaluation supports the formal account: OptABA-PC retains more correct facts, reduces ambiguity in the compatible outputs, and improves graph reconstruction over Causal ABA on common benchmarks.
Figures & tables
| Dataset | |||
|---|---|---|---|
| Cancer (5) | |||
| Survey (6) | |||
| Asia (8) | |||
| ER (5) | |||
| ER (8) | |||
| SF (5) |
Appendix figures & tables17 assets
Supplementary material from the paper’s appendix.
Appendix
| Contested fact | One private MUS | |||
|---|---|---|---|---|
| indep(e,o,{i}) | 1000 | 2070 | 30 | |
| indep(r,i,{e}) | 530 | 2540 | 500 | |
| indep(o,i,{}) | 510 | 2910 | 870 |
| Method | Role and implementation | Final settings |
|---|---|---|
| MPC | Majority-PC ( Colombo and Maathuis, 2014 ) , an order-independent PC variant, learns a skeleton by CI testing, orients colliders by majority evidence across separating sets, and applies Meek propagation to return one CPDAG. | Stable skeleton search; test; ; majority collider rule (implementation uc_rule=5 ); collider priority ; no conditioning-depth limit. |
| ABA-PC | Causal ABA-PC ( Russo et al., 2024 ) receives MPC’s CI trace and releases facts from lowest to highest strength until its Bayes-ball Causal ABA program is coherent. | Same MPC trace; no conditioning-set-size multiplier; strength for and otherwise; integer weight ; incremental Bayes-ball encoding. |
| OptABA-PC | Our method uses the same facts, weights, and candidate-DAG encoding as ABA-PC, replacing sequential release with one minimum-cost correction-set optimisation. | MUS-reified weak constraints; clingo branch-and-bound ( bb ); optN enumeration of optimal stable models; minimum total released weight; four solver threads. |
| FGS | Fast Greedy Search ( Ramsey et al., 2017 ) is the Tetrad/ py-causal fast implementation of GES ( Chickering, 2002b ) ; it greedily inserts and removes edges under a score and returns one CPDAG. | BDeu score ( bdeu-score ); discrete-data interface; sample prior ; structure prior ; unrestricted maximum degree ( -1 ); faithfulness assumed; symmetric first step disabled. |
| ASPCR-DAG | The ASP method of Hyttinen et al. (2014) , restricted here to causally sufficient DAGs, assigns a cost to every graph–test disagreement and returns one optimal DAG. | Exhaustive conditioning schedule ; Bayesian CI test; log weights; prior independence ; Bayesian ; acyclic sufficient encoding; clingo crafty configuration; comparison time limit s. |
| Dataset | Completed | Paired | End-to-end time (s) | BB/original | ||
|---|---|---|---|---|---|---|
| Active paths | Bayes-ball | Active paths | Bayes-ball | |||
| Cancer (5) | 50/50 | 50/50 | 50 | |||
| Earthquake (5) | 50/50 | 50/50 | 50 | |||
| Survey (6) | 50/50 | 50/50 | 50 | |||
| Asia (8) | 50/50 | 50/50 | 50 | |||
| ER (5) | 50/50 | 50/50 | 50 | |||
| Method | Run status | Feasible traces | Full-trace matches | Explicit repairs | Selected repair enforced |
|---|---|---|---|---|---|
| OptABA-PC | 400/400 saved: 368 completed, 32 timeout incumbents | 88/400 | 88/400 | 312/312 | 400/400 |
| ABA-PC | 400/400 saved and completed | 88/400 | 88/400 | 312/312 | 400/400 |
| ASPCR-DAG | 250/250 saved; all optima proved | 32/250 | 32/250 | – | – |
| MPC | 400/400 saved and completed | 88/400 | 80/400 | – | – |
| FGS | 400/400 saved and completed | – | – | – | – |
| Method | Scope | Baseline decision evidence | Forced-fact evidence | Certificate supplied |
|---|---|---|---|---|
| OptABA-PC | , 250 | Minimum repair on 111/111 inconsistent traces; lower cost than ABA-PC on 108 , tied on 3. | 742/742 proved; zero gaps 0/742; median [0.182,0.912]. 11.6% are ; 22.5% are . | Exact user-contestation threshold. |
| ABA-PC | , 250 | Selected repair enforced on 250/250; minimum cost on only 3/111 inconsistent traces (108 higher). | – | Heuristic repair; no exact response threshold. |
| MPC | , 250 | Compatible on 126/139 feasible traces; 13 avoidable gaps; no selected repair. | – | No repair or contestation object. |
| ASPCR-DAG | native, 250 | Full trace on 23/250; graph optimum proved on 250/250. | 4330/4330 proved; zero gaps 0/4330; median [0.890,8.647]. | Post-hoc graph-objective sensitivity. |
| Input status | Saved OptABA-PC repair vs. ABA-PC | MPC output | ||||
|---|---|---|---|---|---|---|
| Dataset | Feasible / inputs | Lower / inconsistent | Same cost | Median saving | Full trace / inputs | Gap / feasible |
| Cancer (5) | 0/50 | 50/50 | 0 | 40.2% | 0/50 | – |
| Earthquake (5) | 47/50 | 1/3 | 2 | 61.8% | 47/50 | 0/47 |
| Survey (6) | 0/50 | 50/50 | 0 | 57.1% | 0/50 | – |
| Asia (8) | 0/50 | 50/50 | 0 | 73.0% | 0/50 | – |
| ER (5) | 16/50 | 26/34 | 8 | 48.4% | 11/50 | 5/16 |
| OptABA-PC contestations | ASPCR-DAG sensitivity probes | ||||
|---|---|---|---|---|---|
| Dataset | Proved | Median | Median | Proved | Median |
| Cancer (5) | 207/207 | 0.297 [0.158,0.609] | 0.072 | 959/959 | 4.041 [1.615,7.946] |
| Earthquake (5) | 4/4 | 4.170 [1.628,6.332] | 3.544 | 80/80 | 3.625 [0.990,6.349] |
| Survey (6) | 507/507 | 0.517 [0.200,1.026] | 0.051 | 2094/2094 | 2.376 [0.537,14.074] |
| ER (5) | 0/0 | – | – | 503/503 | 2.163 [0.773,5.555] |
| SF (5) | 24/24 | 0.734 [0.308,1.344] | 0.182 | 694/694 | 2.437 [0.958,6.108] |
| Dataset | Method | Correct retained | Fact F1 | Time (s) |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| Earthquake (5) | ABA-PC | |||
| OptABA-PC | ||||
| Survey (6) | ABA-PC | |||
| OptABA-PC |
| Dataset | Method | #CPDAGs | CPDAG F1 | CPDAG SHD |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| Earthquake (5) | ABA-PC | |||
| OptABA-PC | ||||
| Survey (6) | ABA-PC | |||
| OptABA-PC |
| Dataset | Method | CPDAG SHD | CPDAG F1 | DAG SHD | DAG F1 | Compat. CPDAGs |
|---|---|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||||
| OptABA-PC | ||||||
| MPC | ||||||
| FGS | – | |||||
| ASPCR-DAG | ||||||
| Earthquake (5) | ABA-PC |
| Dataset | Method | Correct available | Correct kept | False kept |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC | |||
| OptABA-PC | ||||
| ASPCR-DAG |
| Dataset | Method | Precision | Recall | Fact F1 |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC | |||
| OptABA-PC | ||||
| ASPCR-DAG |
| Dataset | Method | SHD avg | SHD best | SHD worst |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| MPC | ||||
| FGS | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC |
| Dataset | Method | F1 avg | F1 best | F1 worst |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| MPC | ||||
| FGS | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC |
| Dataset | Method | SHD avg | SHD best | SHD worst |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| MPC | ||||
| FGS | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC |
| Dataset | Method | F1 avg | F1 best | F1 worst |
|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||
| OptABA-PC | ||||
| MPC | ||||
| FGS | ||||
| ASPCR-DAG | ||||
| Earthquake (5) | ABA-PC |
| Dataset | Method | Time (s) | Returned CPDAGs | Returned DAGs | CI-compat. CPDAGs | CI-compat. DAGs |
|---|---|---|---|---|---|---|
| Cancer (5) | ABA-PC | |||||
| OptABA-PC | ||||||
| MPC | ||||||
| FGS | – | – | ||||
| ASPCR-DAG | ||||||
| Earthquake (5) | ABA-PC |