<p>To incorporate some of @amoeba's suggestions, how about:  </p>

<blockquote>
  <p>The error of an estimate or prediction is its deviation from the true value, which may be unobservable (e.g., regression parameters), or observable (e.g., future realizations). Use the [error-message] tag to ask about software errors. </p>
</blockquote>

<p>That has 234 characters instead of 308.  </p>

<p>I would leave the full wiki as is for the moment.  I think the ideas can be brought together and explained coherently.  I'll have to think about it.  </p>
