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<html><head><title>R: Results from an Experiment on Plant Growth</title>
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<table width="100%" summary="page for PlantGrowth"><tr><td>PlantGrowth</td><td align="right">R Documentation</td></tr></table>

<h2>Results from an Experiment on Plant Growth</h2>

<h3>Description</h3>


<p>Results from an experiment to compare yields (as measured by dried
weight of plants) obtained under a control and two different treatment
conditions.
</p>


<h3>Usage</h3>

<pre>PlantGrowth</pre>


<h3>Format</h3>


<p>A data frame of 30 cases on 2 variables.
</p>

<table summary="Rd table">
<tr>
 <td align="right">
    [, 1] </td><td align="left"> weight </td><td align="left"> numeric </td>
</tr>
<tr>
 <td align="right">
    [, 2] </td><td align="left"> group  </td><td align="left"> factor
  </td>
</tr>

</table>

<p>The levels of <code>group</code> are &lsquo;ctrl&rsquo;, &lsquo;trt1&rsquo;, and &lsquo;trt2&rsquo;.
</p>


<h3>Source</h3>


<p>Dobson, A. J. (1983)
<EM>An Introduction to Statistical Modelling</EM>.
London: Chapman and Hall.
</p>


<h3>Examples</h3>

<pre>
## One factor ANOVA example from Dobson's book, cf. Table 7.4:
require(stats); require(graphics)
boxplot(weight ~ group, data = PlantGrowth, main = "PlantGrowth data",
        ylab = "Dried weight of plants", col = "lightgray",
        notch = TRUE, varwidth = TRUE)
anova(lm(weight ~ group, data = PlantGrowth))
</pre>


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