\begin{table}[htbp]
\centering
\caption{Estimates and confidence intervals of treatment effects}
\begin{tabular}{cccc}
\toprule
& & $ E[Y_\beta] -  E[Y_\alpha]$ & $ E[Y_\gamma] - E[Y_\beta]$\\
\midrule
\multirow{3}{*}{$k=10$} & Est.&0.24 & 0.62\\
& 95\% CI&[-0.35,0.82] & [0.21,1.03]\\
& 90\% CI&[-0.25,0.73] & [0.27,0.96]\\
\midrule
\multirow{3}{*}{$k=20$} &Est. &0.11& 0.69\\
& 95\% CI&[-0.20,0.43] & [0.44,0.95]\\
& 90\% CI&[-0.15,0.38] & [0.48,0.91]\\
\midrule
\multirow{3}{*}{$k=30$} &Est. &0.07& 0.74\\
& 95\% CI&[-0.15,0.29] & [0.55,0.94]\\
& 90\% CI&[-0.12,0.26] & [0.58,0.91]\\
\bottomrule
\end{tabular}
\label{tab:est_ci}
\end{table}