title: How to Increase the thickness of the box lines in an R boxplot?
body: <p>How can I increase the thickness of the lines that outline "box" part of a boxplot using either the base R plot or boxplot function?  That is, how do I thicken the lines of the box that defines the quantiles.</p>
  
  <p>For a plot like this:</p>
  
  <pre><code>boxplot(rnorm(100,50,10), horizontal = TRUE, notch = TRUE)
  </code></pre>
  
  <p>I'm guessing I need to include a <code>pars =</code> statement like </p>
  
  <pre><code>boxplot(rnorm(100,50,10), horizontal = TRUE, notch = TRUE, pars = ...)
  </code></pre>
  
  <p>EDIT: 
  My guess regarding the use of <code>pars =</code> comes from a first glance at the documentation for <code>boxplot</code> which indicates that <code>pars =</code> can call "a list of (potentially many) more graphical parameters, e.g., boxwex or outpch; these are passed to bxp (if plot is true)..."</p>