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<html><head><title>R: The Effect of Vitamin C on Tooth Growth in Guinea Pigs</title>
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<table width="100%" summary="page for ToothGrowth"><tr><td>ToothGrowth</td><td align="right">R Documentation</td></tr></table>

<h2>The Effect of Vitamin C on Tooth Growth in Guinea Pigs</h2>

<h3>Description</h3>


<p>The response is the length of odontoblasts (teeth) in each of 10
guinea pigs at each of three dose levels of Vitamin C (0.5, 1, and 2
mg) with each of two delivery methods (orange juice or ascorbic
acid).
</p>


<h3>Usage</h3>

<pre>ToothGrowth</pre>


<h3>Format</h3>


<p>A data frame with 60 observations on 3 variables.
</p>

<table summary="Rd table">
<tr>
 <td align="right">
    [,1]  </td><td align="left"> len   </td><td align="left"> numeric  </td><td align="left"> Tooth length</td>
</tr>
<tr>
 <td align="right">
    [,2]  </td><td align="left"> supp  </td><td align="left"> factor   </td><td align="left"> Supplement type (VC or OJ).</td>
</tr>
<tr>
 <td align="right">
    [,3]  </td><td align="left"> dose  </td><td align="left"> numeric  </td><td align="left"> Dose in milligrams.
  </td>
</tr>

</table>



<h3>Source</h3>


<p>C. I. Bliss (1952)
<EM>The Statistics of Bioassay</EM>.
Academic Press.
</p>


<h3>References</h3>


<p>McNeil, D. R. (1977)
<EM>Interactive Data Analysis</EM>.
New York: Wiley.
</p>


<h3>Examples</h3>

<pre>
require(graphics)
coplot(len ~ dose | supp, data = ToothGrowth, panel = panel.smooth,
       xlab = "ToothGrowth data: length vs dose, given type of supplement")
</pre>


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