model_graph_test.dot

digraph model_graph {
    graph [overlap=scale, nodesep=0.5, ranksep=0.5]
One_Two [shape=diamond, label="", height=0.2, width=0.3]
One_Two [shape=diamond, label="", height=0.2, width=0.3]
Alpha -> Beta [arrowtail=tee, arrowhead=crowodot]
Alpha -> Gamma [constraint=false, arrowtail=crowodot, arrowhead=crowodot, style=dotted]
One_Two -> Two [arrowtail=crowodot, arrowhead=tee]
One_Two -> One [constraint=false, arrowtail=crowodot, arrowhead=tee]
A -> B [arrowtail=tee, arrowhead=crowodot]
A -> C [arrowtail=tee, arrowhead=odottee]
Beta -> Gamma [arrowtail=crowodot, arrowhead=tee]
Selfish -> Selfish [arrowhead=crowodot]
}