time-tow-lined-braces+timeline+command+text+foreach+tabular+learn.tex

% https://tex.stackexchange.com/a/215994/173708
\documentclass[tikz,border=5mm]{standalone}
\newcommand{\mytab}[1]{%
\begin{tabular}{@{}c@{}}
#1
\end{tabular}
}
\begin{document}
\begin{tikzpicture}
	\draw (0,0) -- (11,0);
	\foreach \x in {0.8,4,5.5,7,10.2}
		\draw(\x cm,3pt) -- (\x cm, -3pt);
	\draw (0.8,0) node[below=3pt] {$T_0$};
	\draw (4,0) node[below=3pt] {$T_1$};
	\draw (5.5,0) node[below=3pt] {$0$};
	\draw (7,0) node[below=3pt] {$T_2$};
	\draw (10.2,0) node[below=3pt] {$T_3$};
	\draw (2.35,0) node[above=6pt, align=center] {
	                        $\left(\mytab{estimation \\ window}\right]$};
\end{tikzpicture}
\end{document}