\documentclass{article}
\usepackage{threeparttable}
\usepackage{multirow}
\usepackage{booktabs}
\usepackage{xcolor}
\begin{document}
\begin{table}[!ht]
\setlength\tabcolsep{0pt}
\centering
\begin{threeparttable}
\begin{tabular}{@{\extracolsep{2ex}}*{4}{lllc}}
\toprule
\textbf{group1} & \textbf{group2} & \textbf{group3} & \textbf{value1} \\
\midrule
\multirow[t]{4}{*}{a} & \multirow[t]{2}{*}{e} & c & 1 \\
 &  & d & 3 \\
 & \multirow[t]{2}{*}{f} & c & 2 \\
 &  & d & 4 \\
\multirow[t]{4}{*}{b} & \multirow[t]{2}{*}{e} & c & 5 \\
 &  & d & 7 \\
 & \multirow[t]{2}{*}{f} & c & 6 \\
 &  & d & 8 \\
\bottomrule
\end{tabular}
\end{threeparttable}
\end{table}
\end{document}