title: PRESS Stat Error - Can't use NA as column index with `[` at position 1
body: <p>I have build the regression model as follows:</p>
  <pre class="lang-r prettyprint-override"><code>model = lm(delay ~ industry + public + quality + finished, data)
  </code></pre>
  <p>and I am trying to run the PRESS statistic function from the <code>qpcR</code> package</p>
  <pre class="lang-r prettyprint-override"><code>&gt; press = PRESS(model, verbose = FALSE)
  </code></pre>
  <p>but I am getting the error -</p>
  <blockquote>
  <p>Error: Can't use NA as column index with <code>[</code> at position 1.
  In addition: Warning message:
  'newdata' had 1 row but variables found have 40 rows</p>
  </blockquote>
  <p>The thing is that I do not have NAs and have not specified newdata</p>
  <pre class="lang-r prettyprint-override"><code>&gt; which(is.na(data))
  
  integer(0)
  </code></pre>
  <p>Any ideas would be appreciated.</p>