_images/08-Instrumental-Variables_2_0.svg

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
 "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<!-- Generated by graphviz version 2.44.1 (20200629.0846)
 -->
<!-- Pages: 1 -->
<svg width="95pt" height="188pt"
 viewBox="0.00 0.00 95.44 188.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 184)">
<polygon fill="white" stroke="transparent" points="-4,4 -4,-184 91.44,-184 91.44,4 -4,4"/>
<!-- ability -->
<g id="node1" class="node">
<title>ability</title>
<ellipse fill="none" stroke="black" cx="54.3" cy="-162" rx="33.29" ry="18"/>
<text text-anchor="middle" x="54.3" y="-158.3" font-family="Times,serif" font-size="14.00">ability</text>
</g>
<!-- educ -->
<g id="node2" class="node">
<title>educ</title>
<ellipse fill="none" stroke="black" cx="27.3" cy="-90" rx="27.1" ry="18"/>
<text text-anchor="middle" x="27.3" y="-86.3" font-family="Times,serif" font-size="14.00">educ</text>
</g>
<!-- ability&#45;&gt;educ -->
<g id="edge1" class="edge">
<title>ability&#45;&gt;educ</title>
<path fill="none" stroke="black" d="M47.76,-144.05C44.68,-136.06 40.93,-126.33 37.48,-117.4"/>
<polygon fill="black" stroke="black" points="40.64,-115.86 33.77,-107.79 34.11,-118.38 40.64,-115.86"/>
</g>
<!-- wage -->
<g id="node3" class="node">
<title>wage</title>
<ellipse fill="none" stroke="black" cx="54.3" cy="-18" rx="29.5" ry="18"/>
<text text-anchor="middle" x="54.3" y="-14.3" font-family="Times,serif" font-size="14.00">wage</text>
</g>
<!-- ability&#45;&gt;wage -->
<g id="edge2" class="edge">
<title>ability&#45;&gt;wage</title>
<path fill="none" stroke="black" d="M57.95,-143.91C59.97,-133.57 62.28,-120.09 63.3,-108 64.64,-92.06 64.64,-87.94 63.3,-72 62.58,-63.5 61.23,-54.31 59.79,-46.01"/>
<polygon fill="black" stroke="black" points="63.21,-45.29 57.95,-36.09 56.33,-46.56 63.21,-45.29"/>
</g>
<!-- educ&#45;&gt;wage -->
<g id="edge3" class="edge">
<title>educ&#45;&gt;wage</title>
<path fill="none" stroke="black" d="M33.7,-72.41C36.81,-64.34 40.63,-54.43 44.13,-45.35"/>
<polygon fill="black" stroke="black" points="47.42,-46.55 47.76,-35.96 40.89,-44.03 47.42,-46.55"/>
</g>
</g>
</svg>