title: Tableau, how to calculate Weighted Standard Deviation
body: <p>I've a problem to calculate weighted standard deviation. Here's the formula I used:</p>
  
  <pre><code>sum([Weight]*(([Variable]-[Mean Score - Variable])^2))
  /
  SUM([Weight])
  </code></pre>
  
  <p>But there's a error pop up message "Cannot mix aggregrate and non-aggregrate"</p>
  
  <p>I wonder what's wrong with my formula?</p>
  
  <p>Thanks</p>