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<table width="100%" summary="page for frets"><tr><td>frets</td><td align="right">R Documentation</td></tr></table>

<h2>
Head Dimensions in Brothers
</h2>

<h3>Description</h3>


<p>The <code>frets</code> data frame has 25 rows and 4 columns.
</p>
<p>The data consist of measurements of the length and breadth of the heads of 
pairs of adult brothers in 25 randomly sampled families.  All measurements
are expressed in millimetres.
</p>


<h3>Usage</h3>

<pre>
frets
</pre>


<h3>Format</h3>


<p>This data frame contains the following columns:
</p>

<dl>
<dt><code>l1</code></dt><dd>
<p>The head length of the eldest son.
</p>
</dd>
<dt><code>b1</code></dt><dd>
<p>The head breadth of the eldest son.
</p>
</dd>
<dt><code>l2</code></dt><dd>
<p>The head length of the second son.
</p>
</dd>
<dt><code>b2</code></dt><dd>
<p>The head breadth of the second son.
</p>
</dd></dl>


<h3>Source</h3>


<p>The data were obtained from
</p>
<p>Frets, G.P. (1921) Heredity of head form in man. <EM>Genetica</EM>, <B>3</B>,
193.
</p>


<h3>References</h3>


<p>Davison, A.C. and Hinkley, D.V. (1997) 
<EM>Bootstrap Methods and Their Application</EM>. Cambridge University Press.
</p>
<p>Whittaker, J. (1990) <EM>Graphical Models in Applied Multivariate Statistics</EM>.
John Wiley.
</p>


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