---
conjecture: r2-edh-b1-12
family: codex
model: "gpt-5.6-sol (codex-cli 0.144.0-alpha.4, ChatGPT-subscription auth)"
model_stamp_corrected: "2026-08-07 — archives were first written stamped gpt-5.5 by a runner bug (the stamper read config.toml's default instead of the -m flag actually passed). The calls themselves ran on gpt-5.6-sol throughout; only the label was wrong. Corrected in place, noted here rather than silently."
received: 2026-08-07
template: PROMPT_TEMPLATE_v1.md sha256 4344aabfacfe88362c56d89b6c89d594a7bf3a221e18a16b0e351482447e512f
rivals_parsed: 3
validation: VALID
---

{
  "rivals": [
    {
      "mechanism": "Diplomas were portable personal documents and may concentrate where veterans retired, were settled, or returned after service, rather than where their units were actively garrisoned. Recruitment and veteran-settlement zones could overlap the frontier provinces highlighted in both partitions.",
      "why_it_explains_the_same_evidence": "Several frontier societies supplied many recruits and received discharged veterans, so both the four training concentrations and the two upper-Danube/eastern-Alpine holdout concentrations could arise from veterans carrying certificates to their post-service residences. The raw find counts alone do not establish that the issuing units or recipients were stationed locally when discharged.",
      "named_confounds": [
        "mobility of diploma recipients after discharge",
        "veteran recruitment-origin and retirement-settlement geography",
        "misidentification of artifact findspot with service location"
      ],
      "discriminating_test": {
        "description": "For each diploma, link its dated issuing unit and recipient, where recoverable, to a chronological unit-station dataset and classify its findspot as fort-associated or civilian/retirement settlement. The stated mechanism predicts predominantly local unit-findspot matches and clustering near contemporary garrisons; the rival predicts many units stationed elsewhere and clustering at civilian settlements or recipient home regions.",
        "computable_on_held_data": false,
        "what_result_favors_rival": "A majority of diplomas in the high-count provinces coming from units stationed outside those provinces, together with findspots concentrated away from contemporary forts, would favor post-service mobility and settlement."
      }
    },
    {
      "mechanism": "The pattern may be an exposure effect from using raw province counts: provinces with more archaeological sites, larger catalogued corpora, or more catalogued metal objects have more opportunities to contain three diplomas. Frontier status would then be correlated with catalogue volume rather than causing diploma deposition.",
      "why_it_explains_the_same_evidence": "A small diploma probability applied to very unequal provincial record totals can generate several provinces with counts of 3 to 45 while most low-exposure provinces have 0 or 1. If the training frontier provinces and both holdout targets are among EDH's most intensively represented provinces, the observed split follows without any special effect of active garrisons.",
      "named_confounds": [
        "raw-count denominator effect",
        "unequal provincial catalogue coverage",
        "province-size and site-density differences",
        "unequal representation of metal inscriptions"
      ],
      "discriminating_test": {
        "description": "For every EDH province, model unique diploma counts with an offset for total catalogued inscriptions and, separately, total catalogued metal objects; then test whether frontier or active-garrison status retains a positive residual effect. Also compare each target with non-frontier provinces having similar catalogue denominators.",
        "computable_on_held_data": true,
        "what_result_favors_rival": "Diploma counts proportional to catalogue or metal-object exposure, with the frontier coefficient near zero and the targets unexceptional among denominator-matched provinces, would favor the exposure mechanism."
      }
    },
    {
      "mechanism": "EDH may have incorporated specialist military-diploma publications or collection inventories in geographically concentrated batches, causing certain provinces to receive many diploma records independently of their ancient deposition rates. An alphabetical province split would place records from the same underlying harvest process on both sides and therefore would not test this mechanism.",
      "why_it_explains_the_same_evidence": "A specialist corpus focused on major Danubian and Alpine find regions could produce the four training concentrations and the two large holdout counts while leaving provinces outside that corpus at 0 or 1. The complete fixed catalogue and alphabetical split preserve, rather than disrupt, any shared bibliographic ingestion pattern.",
      "named_confounds": [
        "specialist-bibliography harvest artifact",
        "geographically uneven EDH data ingestion",
        "publication and collection inventory clustering",
        "possible multiple records for one physical object"
      ],
      "discriminating_test": {
        "description": "Deduplicate records by object identity, findspot, text, dimensions, museum accession, and publication cross-reference; then tabulate diploma counts by source publication, collection, contributor, and ingestion cohort. Re-estimate provincial concentrations after retaining one record per object and controlling for those source batches.",
        "computable_on_held_data": true,
        "what_result_favors_rival": "The high counts being dominated by a few shared publications, collections, or ingestion cohorts, followed by substantial collapse of the provincial concentrations after deduplication or source controls, would favor the catalogue-harvest mechanism."
      }
    }
  ],
  "no_viable_rival": false,
  "notes": ""
}
