Empirical claim #2 — MOFCOM counter-control reflex window
Generated 2026-05-23 06:51 UTC by `scripts/py/intelligence/event_study_mofcom_reflex.py`. Re-run anytime; pure-Python, no network.
Pre-registered cohort
All IPTM actions with issuer_country = CN, action_type ∈ {export-control, sanctions}, severity >= 4, announced_date in [2018-01-01, 2026-12-31], with a full T+60 trading-day window available in the ETF dataset.
Matched: 14 actions in cohort; 1 excluded for insufficient post-event ETF data (announced after 2026-02-19). Final n = 13.
The claim
Severity-4+ MOFCOM export-control or sanctions actions are historically followed, over the 5- to 60-trading-day windows, by:
- EWZ (Brazil) / EZA (South Africa) / EWC (Canada) / EWA (Australia) — the four largest non-China alternative suppliers of the restricted critical materials — outperforming the ACWI global benchmark; AND
- SPY (US, the primary downstream-consumer market for the restricted Chinese exports) trailing ACWI.
MCHI is reported alongside for transparency. The claim is about the alternative-supplier response; MCHI's direction is not the headline.
This is a historical association, not a forecast.
Results — abnormal returns vs. ACWI
Median log-return on each ETF minus log-return on ACWI over the same window. Two-sided sign test against H0: median = 0 (binomial exact). Wilcoxon signed-rank p is the more powerful rank-based test (normal approx; reported when n >= 6 non-zero observations).
Horizon: T+5d
| ETF | n | median (%) | mean (%) | IQR (%) | % neg | sign-test p | Wilcoxon p |
|---|---|---|---|---|---|---|---|
| EWZ | 13 | +0.48 | +0.34 | 2.38 | 38% | 0.581 | 0.552 |
| EZA | 13 | +1.75 | +2.35 | 3.29 | 8% | 0.003 | 0.003 |
| EWC | 13 | +0.20 | +0.01 | 1.92 | 46% | 1.000 | 0.861 |
| EWA | 13 | +0.20 | +0.12 | 1.78 | 46% | 1.000 | 0.650 |
| MCHI | 13 | +0.91 | +0.39 | 2.87 | 31% | 0.267 | 0.463 |
| SPY | 13 | -0.06 | -0.06 | 0.42 | 62% | 0.581 | 0.382 |
Horizon: T+20d
| ETF | n | median (%) | mean (%) | IQR (%) | % neg | sign-test p | Wilcoxon p |
|---|---|---|---|---|---|---|---|
| EWZ | 13 | +1.51 | +1.93 | 8.19 | 46% | 1.000 | 0.173 |
| EZA | 13 | +4.48 | +3.24 | 5.16 | 23% | 0.092 | 0.028 |
| EWC | 13 | -0.83 | +0.16 | 2.52 | 62% | 0.581 | 0.600 |
| EWA | 13 | -0.59 | +0.53 | 4.17 | 62% | 0.581 | 0.972 |
| MCHI | 13 | -1.77 | +0.84 | 4.74 | 62% | 0.581 | 0.650 |
| SPY | 13 | -0.59 | -0.66 | 1.48 | 69% | 0.267 | 0.101 |
Horizon: T+60d
| ETF | n | median (%) | mean (%) | IQR (%) | % neg | sign-test p | Wilcoxon p |
|---|---|---|---|---|---|---|---|
| EWZ | 13 | +8.72 | +6.09 | 13.52 | 23% | 0.092 | 0.046 |
| EZA | 13 | +6.16 | +4.93 | 14.32 | 31% | 0.267 | 0.101 |
| EWC | 13 | +4.33 | +2.31 | 6.48 | 38% | 0.581 | 0.055 |
| EWA | 13 | +2.72 | +1.56 | 7.52 | 38% | 0.581 | 0.311 |
| MCHI | 13 | -6.27 | -3.28 | 5.85 | 77% | 0.092 | 0.249 |
| SPY | 13 | -1.61 | -1.27 | 2.65 | 69% | 0.267 | 0.046 |
Results — raw log-returns (for reference, not abnormal)
| Horizon | EWZ | EZA | EWC | EWA | MCHI | SPY | ACWI |
|---|---|---|---|---|---|---|---|
| T+5d | +0.77% | +2.28% | -0.24% | -0.34% | +0.64% | -0.30% | -0.44% |
| T+20d | +3.87% | +3.87% | +0.62% | +1.01% | +2.72% | -0.13% | -0.01% |
| T+60d | +12.94% | +9.89% | +7.34% | +1.73% | -2.56% | +0.88% | +1.86% |
Events used
| # | Date | Type | Severity | Action |
|---|---|---|---|---|
| 1 | 2020-10-17 | export-control | 5 | 2020-10-17-china-export-control-law |
| 2 | 2023-07-03 | export-control | 4 | 2023-07-03-china-mofcom-gallium-germanium-export-controls |
| 3 | 2023-10-20 | export-control | 4 | 2023-10-20-china-mofcom-graphite-export-controls |
| 4 | 2024-10-19 | export-control | 5 | 2024-10-19-china-dual-use-export-control-regulations |
| 5 | 2024-12-03 | export-control | 5 | 2024-12-03-china-mofcom-ge-ga-sb-export-ban-us |
| 6 | 2025-02-04 | export-control | 4 | 2025-02-04-china-mofcom-tungsten-tellurium-bismuth-molybdenum-indium-export-controls |
| 7 | 2025-02-04 | sanctions | 4 | 2025-02-04-china-mofcom-uel-announcement-2-2025-pvh-illumina |
| 8 | 2025-03-23 | sanctions | 4 | 2025-03-23-china-afsl-implementation-regulations |
| 9 | 2025-04-04 | export-control | 5 | 2025-04-04-china-mofcom-heavy-rare-earths-export-licensing |
| 10 | 2025-10-09 | export-control | 5 | 2025-10-09-china-mofcom-rare-earths-extraterritorial-export-controls |
| 11 | 2025-10-26 | export-control | 4 | 2025-10-26-china-mofcom-announcement-68-tungsten-antimony-silver-ste-quota |
| 12 | 2025-12-09 | export-control | 4 | 2025-12-09-china-mofcom-steel-export-licensing-announcement-79 |
| 13 | 2026-01-06 | export-control | 5 | 2026-01-06-china-mofcom-announcement-1-2026-japan-dual-use-export-controls |
Honest caveats
1. Small sample (n=13). Effect-size estimates have wide intervals; sub-cohort analysis (e.g. export-control only vs. sanctions only) would be severely under-powered. The reported medians are point estimates, not confidence-bounded.
2. Overlapping event windows. The 2024-12-03 Ge/Ga/Sb ban, the 2025-02-04 tungsten/Te/Bi/Mo/In package, the 2025-04-04 heavy REE licensing rule, and the 2025-10-09 + 2025-10-26 rare-earths + tungsten/Sb package cluster within 60 trading days of each other. Observations are NOT independent, so the reported sign-test and Wilcoxon p-values are anti-conservative — they understate the true probability under the null.
3. No factor-return adjustment. Abnormal returns are computed against ACWI only, not against a multi-factor model (FF3 / FF5 / momentum / commodity-beta). Most of the 2024-2026 EWZ / EZA / EWA outperformance loads on the commodity factor, which would attenuate under a richer benchmark. The reported numbers should be read as raw associations, not factor-purged alphas.
4. Cohort-period confounding. The 2020-2026 window contains COVID, the 2022 commodity-cycle and inflation regime, the 2024-2025 REE price spike (which had multiple drivers beyond MOFCOM's actions), and the Russia war (which independently re-priced commodity exporters). The event-study claim is conditional on these joint regimes.
5. No out-of-sample validation. Future MOFCOM packages may exhibit different post-event dynamics if (a) the regime saturates (post-2026 tightening reads as marginal rather than novel), (b) alternative-supplier capacity comes online and absorbs the price-tightness pop, or (c) China's extraterritorial reach (the 2025-10-09 architecture, claim-#1's case-#4 structural parallel) re-prices alternative-supplier ETFs in the opposite direction by tagging their downstream customers.
6. Cohort criteria pre-registered; test-ticker list is post-hoc. issuer_country = CN, action_type in {export-control, sanctions}, severity >= 4, date window pre-specified before the analysis was run. But the test ETFs (EWZ / EZA / EWC / EWA) were chosen post-hoc because the case-#1 work identified these as the regime's alternative-supplier perimeter. A random draw of other ex-China commodity-exporting countries (Chile, Peru, Indonesia) would not necessarily reproduce the same magnitudes — those ETFs sit in different policy regimes (lithium-triangle nationalisation, hilirisasi) that produce orthogonal noise.
7. Symmetry vs. claim #1 is by design but is NOT mechanically required. Claim #1 found that supplier-country ETFs (EWY / EWT / EWN) outperform ACWI following US BIS controls on China; the structural mirror is that alternative-supplier ETFs (EWZ / EZA / EWC / EWA) would outperform following MOFCOM counter-controls. The two claims are joint evidence for case-#1's reflex thesis only if both signals hold; if one holds and the other does not, the reflex thesis is one-sided and the case-#1 prose should be re-scoped accordingly.