1\begin{table}[htbp]\centering\small2\caption{Final (held-out): WIS relative to Random walk (trailing RMS)}3\label{tab:final_cmp_wis_heldout}4\begin{adjustbox}{max width=\textwidth}5\begin{tabular}{lcccc}6\toprule7Model & $H=5$ & $H=15$ & $H=30$ & $H=60$ \\8\midrule9Seasonal volatility & -2.55\% (-19.8) & -2.85\% (-22.4) & -2.89\% (-18.8) & -3.01\% (-13.9) \\10EWMA-$t$ & -3.51\% (-27.3) & -3.56\% (-24.6) & -3.21\% (-22.0) & -2.80\% (-13.7) \\11HAR-RV & -2.94\% (-25.9) & -3.94\% (-33.7) & -3.90\% (-27.9) & -3.99\% (-19.3) \\12GARCH(1,1)-$t$ & -3.19\% (-21.4) & -3.45\% (-18.8) & -3.01\% (-19.6) & -2.47\% (-11.1) \\13Ridge & -3.14\% (-23.4) & -3.95\% (-31.5) & -3.99\% (-26.5) & -4.10\% (-18.7) \\14Elastic net & -3.14\% (-23.3) & -3.95\% (-31.3) & -3.98\% (-26.3) & -4.12\% (-18.8) \\15LightGBM & -2.28\% (-15.3) & -3.77\% (-20.6) & -3.70\% (-20.8) & -3.80\% (-15.0) \\16MLP (1m) & -4.02\% (-37.5) & -4.00\% (-37.0) & -3.91\% (-31.2) & -3.84\% (-21.7) \\17TCN (1m) & -4.16\% (-33.8) & -4.04\% (-35.0) & -3.88\% (-31.1) & -3.75\% (-21.8) \\18MRPT-S (1m+5m+30m) & -4.25\% (-30.1) & -4.16\% (-35.5) & -4.05\% (-31.0) & -3.99\% (-21.2) \\19MRPT-S (1m only) & -4.23\% (-30.0) & -4.16\% (-35.3) & -4.05\% (-30.5) & -3.98\% (-20.7) \\20MRPT-B (1m+5m+30m) & -4.21\% (-30.4) & -4.11\% (-38.4) & -4.04\% (-32.0) & -3.99\% (-22.6) \\21\bottomrule22\end{tabular}23\end{adjustbox}24\begin{minipage}{0.95\textwidth}\scriptsize Relative change in mean WIS versus the reference (negative = better); Diebold--Mariano $t$-statistic with HAC variance in parentheses.\end{minipage}25\end{table}