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Trazar un árbol de probabilidad con TikZ

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Trazar un árbol de probabilidad con TikZ

El siguiente código debería producir un árbol de probabilidad de tres pasos, pero no se puede compilar. ¿Alguien tiene una idea de por qué no funciona?

\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{tikz}
\usetikzlibrary{trees}
\begin{document}
\pagestyle{empty}

\begin{tikzpicture}[scale=1.5,font=\footnotesize]

% Specify spacing for each level of the tree

\tikzstyle{level 1}=[level distance=12mm,sibling distance=43mm]

\tikzstyle{level 2}=[level distance=15mm,sibling distance=20mm]

\tikzstyle{level 3}=[level distance=15mm,sibling distance=10mm]


\tikzset{

  solid node/.style={circle,draw,inner sep=1,fill=black},

  }


   % The Tree

     \node(0)[solid node]{}

   child{node(1)[solid node,label=left:{$V=1$}]{}

child{node[solid node,label=left:{$s_1=H$}]{}

child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$q$}}

 child{node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$1-q$}}

 edge from parent node [left]{$p$}

 }

 child{node[solid node,label=right:{$s_1=H$}]{}

child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$q$}}

child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$1-q$}}

edge from parent node [right]{$1-p$}

}

edge from parent node [left, yshift=3]{$\frac{1}{2}$}

}

child{node(2)[solid node,label=right:{$V=-1$}]{}

child{node[solid node,label=left:{$s_1=L$}]{}

child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$1-q$}}

child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$q$}}

edge from parent node [left]{$p$}

}

child{node[solid node,label=right:{$s_1=L$}]{}

child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$1-q$}}

child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$q$}}

edge from parent node [right]{$1-p$}

}

edge from parent node [right, yshift=3]{$\frac{1}{2}$}

};


\end{tikzpicture}

\end{document}

Respuesta1

Simplemente no le gustan todas las líneas en blanco. Cuando los elimino, su código se compila bien. También actualicé para eliminar el uso obsoleto de \tikzstyle, pero eso no es necesario para la compilación.

\documentclass[tikz,border=10pt,multi]{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usetikzlibrary{trees}
\begin{document}
\begin{tikzpicture}
  [
    scale=1.5,
    font=\footnotesize,
    level 1/.style={level distance=12mm,sibling distance=43mm},
    level 2/.style={level distance=15mm,sibling distance=20mm},
    level 3/.style={level distance=15mm,sibling distance=10mm},
    solid node/.style={circle,draw,inner sep=1,fill=black},
  ]

  \node(0)[solid node]{}

  child{node(1)[solid node,label=left:{$V=1$}]{}
    child{node[solid node,label=left:{$s_1=H$}]{}
      child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$q$}}
      child{node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$1-q$}}
      edge from parent node [left]{$p$}
    }
    child{node[solid node,label=right:{$s_1=H$}]{}
      child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$q$}}
      child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$1-q$}}
      edge from parent node [right]{$1-p$}
    }
    edge from parent node [left, yshift=3]{$\frac{1}{2}$}
  }
  child{node(2)[solid node,label=right:{$V=-1$}]{}
    child{node[solid node,label=left:{$s_1=L$}]{}
      child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$1-q$}}
      child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$q$}}
      edge from parent node [left]{$p$}
    }
    child{node[solid node,label=right:{$s_1=L$}]{}
      child{node[solid node,label=below:{$s_2=U$}]{} edge from parent node [left]{$1-q$}}
      child{ node[solid node,label=below:{$s_2=D$}]{} edge from parent node [right]{$q$}}
      edge from parent node [right]{$1-p$}
    }
    edge from parent node [right, yshift=3]{$\frac{1}{2}$}
  };

\end{tikzpicture}
\end{document}

árbol de probabilidad

Respuesta2

Aquí hay una forma alternativa de dibujar este árbol usando elistgamepaquete:

ingrese la descripción de la imagen aquí

\documentclass{standalone}

\usepackage{istgame}

\begin{document}   

\begin{istgame}[scale=1.5,font=\footnotesize]
\xtdistance{15mm}{43mm}
\istroot(0)
  \istb{\frac12}[al]
  \istb{\frac12}[ar]
  \endist
\xtdistance{15mm}{20mm}
\istroot(1)(0-1)<180>{$V=1$}
  \istb{p}[l]
  \istb{1-p}[r]
  \endist
\istroot(2)(0-2)<0>{$V=-1$}
  \istb{p}[l]
  \istb{1-p}[r]
  \endist
\xtdistance{15mm}{10mm}
\istroot(a)(1-1)<180>{$s_1=H$}
  \istb{q}[l]{s_2=U}
  \istb{1-q}[r]{s_2=D}
  \endist
\istroot(b)(1-2)<0>{$s_1=H$}
  \istb{q}[l]{s_2=U}
  \istb{1-q}[r]{s_2=D}
  \endist
\istroot(c)(2-1)<180>{$s_1=L$}
  \istb{1-q}[l]{s_2=U}
  \istb{q}[r]{s_2=D}
  \endist
\istroot(d)(2-2)<0>{$s_1=L$}
  \istb{1-q}[l]{s_2=U}
  \istb{q}[r]{s_2=D}
  \endist
\end{istgame}    

\end{document}

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