212 21 25 7 36 158 35 102 35 ...
- attr(*, &quot;dimnames&quot;)=List of 2
..$ exposure: chr [1:5] &quot;0-9&quot; &quot;10-19&quot; &quot;20-29&quot; &quot;30-39&quot; ...
..$ grade   : chr [1:4] &quot;None&quot; &quot;Grade 1&quot; &quot;Grade 2&quot; &quot;Grade 3&quot;
</p>


<h3>Details</h3>

<p><code>exposure</code> and <code>grade</code> should be regarded as ordered factors.
Beh and Lombardo (2022) use this data to illustrate a polynomial
biplot for ordered categories.
</p>
<p>The data summarized he