title: Scipy linear regression does not include `intercept_stderr` property
body: <p>I'm trying to perform a linear regression on a set of two-dimensional points using scipy. As stated by the documentation <a href="https://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.linregress.html" rel="nofollow noreferrer">here</a>, the appropriate call is</p>
  <pre class="lang-py prettyprint-override"><code>regression_results = scipy.stats.linregress(x_values, y_values)
  </code></pre>
  <p>The documentation states that the <code>regression_results</code> object contains the following values: <code>slope, intercept, rvalue, pvalue, stderr, intercept_stderr</code>. All of these are present <strong>except the last</strong>.</p>
  <p>These values are all present in the dict, but <code>intercept_stderr</code> is simply not. I cannot for the life of me fathom why. Here is the simple code I attempted to run:</p>
  <pre class="lang-py prettyprint-override"><code>from scipy import stats
  
  # given two lists nmeq_x and nmeq_y... 
  
  result = stats.linregress(nmeq_x, nmeq_y)
  print(result.intercept, result.intercept_stderr)
  </code></pre>
  <p>I get the error:</p>
  <pre><code>---------------------------------------------------------------------------
  AttributeError                            Traceback (most recent call last)
  &lt;ipython-input-18-7df9d260a3bb&gt; in &lt;module&gt;
        1 result = stats.linregress(nmeq_x, nmeq_y)
  ----&gt; 2 print(result.intercept, result.intercept_stderr)
  
  AttributeError: 'LinregressResult' object has no attribute 'intercept_stderr'
  </code></pre>