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# Hypothesis registry (model category labelling)

id statement primary statistic p raw p Holm status
H1 Online assortment composition differs across regions beyond what merchant counts imply Cramér's V (M) = 0.112, store-reshuffle p = 0.0005; (T) V = 0.191, p = 0.429; (L) p = 0.199 0.4293 0.8586 not supported (preregistered joint criterion)
H2 Regional diversity is associated with regional scale Spearman rho(rarefied entropy, log population) = 0.04, 95% CI [-0.65; 0.62], n = 16 0.8995 0.8995 inconclusive
H3 Merchant catalogue sizes are highly skewed Gini = 0.849 [0.811; 0.878]; top-10% share = 0.789 [0.730; 0.836] supported
H4 Related diversification (exploratory) LPM density coefficient 0.102 (SE 0.031), placebo p = 0.005; 151 entries; 1 region-level entries exploratory: consistent with relatedness at the store level; region level untestable
H5-T1 Matched-product prices are geographically structured Wald(14) = 164.2, wild-cluster-bootstrap p = 0.0975; 1064 groups, 143 stores, 9 regions with >= 5 stores 0.0975 0.2925 not supported
H5-T2 Matched-product prices are competitively structured (reseller vs producer) reseller coefficient -0.116 (SE 0.026), wild-bootstrap p = 0.0041 0.0041 0.0164 supported
H6 Local-origin price premium not estimated untestable (declared ex ante)
H7 Validated digital-assortment complexity indicator ECI bootstrap rank stability median rho = 0.68 (criterion 0.8); lambda2 null p = 0.00; LOO predictive rho = 0.01 not validated: ECI unstable at 17 x 20; omitted from QDACI
QDACI Composite index median agreement across weightings rho = 0.29 (rule 0.7); bootstrap rank stability 0.45 components published; composite withheld

Notes:

  • H1: Preregistered criterion required p < 0.05 under both merchant-equal and trimmed-listing weights; merchant-equal p = 0.0005, trimmed p = 0.429. The merchant-equal dependence is reported as a descriptive, non-preregistered finding; the listing-weighted null is a power-limited result (null SD much larger under L/T).
  • H2: CI includes zero and economically meaningful values in both directions; n = 16 regions. No association with business counts or density either (see table).
  • H3: Both preregistered thresholds (Gini >= 0.70, top-10% >= 0.50) exceeded with CIs entirely above them; power-law tail favoured over log-normal on the tail.
  • H4: Fewer than 10 region-level entries (preregistered untestability rule); store-level association over 5 weeks, no causal claim.
  • H5-T1: Region effects identified only through groups spanning regions; posted prices, no shipping/taxes. Wild cluster bootstrap with group-demeaned disturbances (corrected after referee 1); leave-one-region-out Wald: {'Abitibi-Témiscamingue': 163.81, 'Capitale-Nationale': 141.04, 'Centre-du-Québec': 128.76, 'Chaudière-Appalaches': 162.46, 'Côte-Nord': 152.42, 'Estrie': 162.58, 'Gaspésie–Îles-de-la-Madeleine': 162.96, 'Lanaudière': 87.95, 'Laurentides': 161.58, 'Laval': 163.22, 'Mauricie': 163.99, 'Montérégie': 162.41, 'Outaouais': 51.35, 'Saguenay–Lac-Saint-Jean': 163.63}.
  • H5-T2: Resellers/collectives post lower prices than producers for the same product.
  • H6: No product-level provenance; a store-certification contrast is reported descriptively and is not H6.
  • H7: Fitness and plain diversity are more stable but still below the criterion; the region-category matrix is not more nested than the store-reshuffle null.
  • QDACI: Components describe observed online catalogues of Quebec-based merchants, not production or output. Complexity omitted because the ECI failed the preregistered stability criterion.
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