\section{Additional Centroid Uncertainty Plots}\label{ap:centroids}

We provide complete histogram and eCDF visualisations for all centroid-head uncertainties ($u_{\mathrm{peak}}$, $u_{\mathrm{mass}}$, and their linear combination $u_{\mathrm{cent}}$), separately for PanNuke and Ki-67 and for both evidential variants.  
Figures~\ref{fig:cent_inst_pannuke_ours} and \ref{fig:cent_inst_ki67_ours} correspond to \textit{Ours}, and Figures~\ref{fig:cent_inst_pannuke_oursw} and \ref{fig:cent_inst_ki67_oursw} show the same plots for \textit{Ours w}.  
Because centroid uncertainty arises from geometric cues rather than class probabilities, all evaluations are conducted at the \textit{instance level}.  
Across datasets, errors consistently appear in the high-uncertainty tail, while correctly detected nuclei cluster at lower values. 
% ============================================================
% FIGURE 1 — PANNUKE — OURS
% ============================================================
\begin{figure}[t]
    \centering
    % Top row: histograms
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/hist_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/hist_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/hist_all.png}


    % Bottom row: eCDFs
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/ecdf_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/ecdf_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_pannuke/ecdf_all.png}

    \caption{Instance-level centroid-head uncertainties on PanNuke for \textit{Ours}.  
    Top: histograms for $u_{\mathrm{peak}}, u_{\mathrm{mass}}, u_{\mathrm{cent}}$.  
    Bottom: eCDFs. Errors in red, correct nuclei in blue.}
    \label{fig:cent_inst_pannuke_ours}
\end{figure}

% ============================================================
% FIGURE 3 — KI67 — OURS
% ============================================================
\begin{figure}[t]
    \centering
    % Top row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/hist_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/hist_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/hist_all.png}


    % Bottom row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/ecdf_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/ecdf_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_ki67/ecdf_all.png}

    \caption{Instance-level centroid-head uncertainties on Ki-67 for \textit{Ours}.  
    Top: histograms. Bottom: eCDFs. Errors in red, correct nuclei in blue.}
    \label{fig:cent_inst_ki67_ours}
\end{figure}


% ============================================================
% FIGURE 2 — PANNUKE — OURS W
% ============================================================
\begin{figure}[t]
    \centering
    % Top row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/hist_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/hist_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/hist_all.png}


    % Bottom row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/ecdf_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/ecdf_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_pannuke/ecdf_all.png}

    \caption{Instance-level centroid-head uncertainties on PanNuke for \textit{Ours w}.  
    Top: histograms. Bottom: eCDFs. Errors in red, correct nuclei in blue.}
    \label{fig:cent_inst_pannuke_oursw}
\end{figure}


% ============================================================
% FIGURE 4 — KI67 — OURS W
% ============================================================
\begin{figure}[t]
    \centering
    % Top row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/hist_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/hist_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/hist_all.png}


    % Bottom row
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/ecdf_peak.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/ecdf_mass.png}\hfill
    \includegraphics[width=0.30\textwidth]{figures/plots/cen_ins_w_ki67/ecdf_all.png}

    \caption{Instance-level centroid-head uncertainties on Ki-67 for \textit{Ours w}.  
    Top: histograms. Bottom: eCDFs. Errors in red, correct nuclei in blue.}
    \label{fig:cent_inst_ki67_oursw}
\end{figure}
