I just have a little question. I do not know how exactly it works, but may I also make such a circle like on the photo below? The one which I have is not rounded like this and the line is very tight at the numbers. Hope you understand what I mean. Thank you for your help!!
\documentclass[a4paper]{article}
\usepackage{geometry} \geometry{a4paper, top=25mm, left=25mm, right=25mm, bottom=20mm, headsep=10mm, footskip=12mm}
\usepackage[ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage[latin1]{inputenc}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{multirow,array}
\usepackage{arydshln}
\usepackage{tikz}
\dashlinegap=1pt
\usepackage{acronym}
\newcommand\mybox[3][]{%
\tikz[anchor=base,baseline]\node[inner sep=2pt,draw=#2,#1]{$\displaystyle#3\mathstrut$};}
\colorlet{mycol}{black}
\begin{document}
\begin{table}
\renewcommand\arraystretch{1.5}
\setlength{\tabcolsep}{4mm}
\begin{tabular}{*{5}{>{$}c<{$}}}
& & \multicolumn{2}{c}{Player II}& \\
& & \multicolumn{1}{c}{H} & \multicolumn{1}{c}{T} & \underset{s_1 \in S_1}{min} \, u(s_1, s_2) \\\cline{3-4}
\multirow{2}*{Player I}
& H & \multicolumn{1}{|c|}{1} & \multicolumn{1}{c|}{-1} &\multicolumn{1}{l}{-1} \\ \cline{3-4}
& T & \multicolumn{1}{|c|}{-1} & \multicolumn{1}{c|}{-1} &\multicolumn{1}{l}{-1} \\ \cline{3-4}
\multicolumn{1}{r@{}}{$\underset{s_2 \in S_2}{min} \, u(s_1, s_2)$} & & 1 &1 &
\multicolumn{1}{l}{\mybox[rounded corners]{mycol}{1,1}}
\end{tabular}
\end{table}
\end{document}




