# How to design a decision node with both descrete and continuum action set?

I want to use istgame of tikz to design a decision node as a part of an extensive form game theory model in which the mover has 2 possible actions: 1. reject or 2. select a real number from a continuum of (0,1) interval. I want to use arc, not gray triangle or sth else. Thank you if you help me. I mean sth like this:

• Can you add a minimal working example which shows us how far you already got? E.g. if you already know how to draw your diagram with the gray triangle, I'm sure we can help you to change it into an arc. Aug 6 at 10:46
• Why did you re-add the beamer tag? In its current state, there is nothing about beamer in the question. Aug 6 at 10:46
• No I do not know how to do it with triangle. I just said it to stress on arc-type answeres. tnx Aug 6 at 10:48
• There are a lot of examples in the istgame documentation, maybe one of them can get you started? mirrors.ctan.org/graphics/pgf/contrib/istgame/istgame-doc.pdf Aug 6 at 10:55
• Ive read it previously. It was not useful for my specific problem Aug 6 at 10:57

This is my try of using the istgame package: (I do not know the root of your game tree.)

\documentclass{standalone}

\usepackage{amsmath}
\usepackage{istgame}

\begin{document}

\begin{istgame}[font=\scriptsize]
\setistgrowdirection{-60}
\cntmdistance*{20mm}{20mm}
\istroot(0)
\istb*<grow=-135>{reject}[above,sloped] \endist
\cntmAistb{0}[left,near end]{1}[above right,near end]
\cntmApreset{.7}
\istrootcntmA(0)
\istbA*(1.5){}{\binom{a}{b}}            \endist
\istroot(0)
\istb<grow=45>                          \endist
\setistgrowdirection{30}
\istroot(1)(0-1)
\istb[dashed]  \istb[dashed]            \endist
\end{istgame}
\end{document}
`