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<html><head><title>R: Effectiveness of Insect Sprays</title>
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<table width="100%" summary="page for InsectSprays"><tr><td>InsectSprays</td><td align="right">R Documentation</td></tr></table>

<h2>Effectiveness of Insect Sprays</h2>

<h3>Description</h3>


<p>The counts of insects in agricultural experimental units treated with
different insecticides.
</p>


<h3>Usage</h3>

<pre>InsectSprays</pre>


<h3>Format</h3>


<p>A data frame with 72 observations on 2 variables.
</p>

<table summary="Rd table">
<tr>
 <td align="right">
    [,1]  </td><td align="left"> count  </td><td align="left"> numeric  </td><td align="left"> Insect count</td>
</tr>
<tr>
 <td align="right">
    [,2]  </td><td align="left"> spray  </td><td align="left"> factor   </td><td align="left"> The type of spray
  </td>
</tr>

</table>



<h3>Source</h3>


<p>Beall, G., (1942)
The Transformation of data from entomological field experiments,
<EM>Biometrika</EM>, <B>29</B>, 243&ndash;262.
</p>


<h3>References</h3>


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


<h3>Examples</h3>

<pre>
require(stats); require(graphics)
boxplot(count ~ spray, data = InsectSprays,
        xlab = "Type of spray", ylab = "Insect count",
        main = "InsectSprays data", varwidth = TRUE, col = "lightgray")
fm1 &lt;- aov(count ~ spray, data = InsectSprays)
summary(fm1)
opar &lt;- par(mfrow = c(2,2), oma = c(0, 0, 1.1, 0))
plot(fm1)
fm2 &lt;- aov(sqrt(count) ~ spray, data = InsectSprays)
summary(fm2)
plot(fm2)
par(opar)
</pre>


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