changing font size in regression tree plot
<pre><code>library(rpart)
library(rpart.plot)
fit &lt;- rpart(Kyphosis ~ Age + Number + Start, data = kyphosis)
prp(fit, type = 4, extra = 101, leaf.round = 1, fallen.leaves = TRUE,
    varlen = 0, tweak = 0.8)
</code></pre>

<p><a href="https://i.stack.imgur.com/PZK2T.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PZK2T.png" alt="enter image description here"></a></p>

<p>I'm trying to get the text to fit inside the rounded squares. I tried lowering the <code>tweak</code> and <code>cex</code> values, but it appears that the rounded squares get smaller along with the text. How can I make the font size smaller?</p>