\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$} & Est.&0.14 & 0.46\\
& 95\% CI&[-0.46,0.75] & [-0.21,1.13]\\
& 90\% CI&[-0.37,0.65] & [-0.10,1.02]\\
\midrule
\multirow{3}{*}{$k=20$} &Est. &0.08& 0.58\\
& 95\% CI&[-0.24,0.40] & [0.22,0.95]\\
& 90\% CI&[-0.19,0.35] & [0.28,0.89]\\
\midrule
\multirow{3}{*}{$k=30$} &Est. &0.04& 0.76\\
& 95\% CI&[-0.19,0.26] & [0.50,1.02]\\
& 90\% CI&[-0.15,0.22] & [0.54,0.98]\\
\bottomrule
\end{tabular}
\label{tab:est_ci}
\end{table}