다음 단계는...

반복되는 코드를 대체하는 명령으로 코딩을 간단하게 합니다.

\documentclass{article}

\usepackage{xparse}

\usepackage{tikz}

\tikzstyle{hollow node}=[circle,draw,fill=white,inner sep=.85,outer sep=0pt]

\tikzstyle{solid node}=[circle,draw,inner sep=.75,fill=black]

\newcommand\move[3]{edge from parent [#1] node [#2] {$#3$}}

\newcommand\payoff[2]{node[inner sep=0pt, outer sep=0pt, label={#1:{$#2$}}]{}}

\newcommand\xxxdistance[3][1]

    {\tikzstyle{level #1}=[level distance=#2,sibling distance=#3]}

\NewDocumentCommand\xxxRoot{O{down}mO{}D<>{}G{}}

    {\node #2 [solid node,#3,{label={#4:{#5}}}] {} [grow=#1]}

\begin{document}

%% tikz (parent-child) - new

\begin{tikzpicture}[>=stealth,shorten >=1pt,font=\scriptsize]

\xxxdistance{15mm}{30mm}

\xxxRoot{(0)}[hollow node]{Child}

    child{\payoff{below}{(0,2)}\move{->}{left}{Good}}

    child{\move{->}{right}{Bad}};

\xxxRoot{(1) at (0-2)}<30>{Parent}

    child{\payoff{below}{(1,1)}\move{->}{left}{Forgive}}

    child{\payoff{below}{(-1,-1)}\move{->}{right}{Punish}};

\end{tikzpicture}

\end{document}