1\begin{table}[htbp]\centering\scriptsize2\caption{H5 --- Matched-product price dispersion across merchants}\label{tab:h5}3\begin{tabular}{lrrrrrrrrrrrrr}\toprule4Spec. & Obs. & Groups & Stores & Regions & Wald region (df) & $p$ wild-boot & Reseller (SE) & $p$ wild-boot & Certified (SE) & log catalogue (SE) & Within $R^2$ & Gap median / p90 & Share gap $>$5\% \\\midrule5primary\_AB & 2\,203 & 1\,064 & 143 & 15 & 164.4 (14) & 0.0045 & -0.116 (0.026) & 0.0012 & -0.073 (0.023) & 0.002 (0.008) & 0.166 & 0.047 / 0.288 & 0.49 \\6sens\_ABC & 2\,512 & 1\,189 & 156 & 15 & 83.3 (14) & 0.0162 & -0.101 (0.025) & 0.0029 & -0.028 (0.018) & 0.009 (0.007) & 0.139 & 0.051 / 0.333 & 0.50 \\7\bottomrule\end{tabular}8\begin{minipage}{0.95\textwidth}\vspace{2pt}\footnotesize\textit{Notes:} Dependent variable: log posted price at the snapshot. Match-group fixed effects absorbed; region and platform dummies, log catalogue size, reseller/collective and certification indicators. SE clustered by store; $p$-values from a wild cluster bootstrap (Rademacher, 9\,999 draws, restricted residuals). primary\_AB = tiers A (shared SKU) and B (same brand, identical title); sens\_ABC adds fuzzy tier C. Gap = within-group max--min log price.\end{minipage}9\end{table}10