title: How do I tell angular to set default value for drop down when no match is found in model?
body: <p>I have the following select: </p>
  
  <pre><code>&lt;select class="form-control" id="selSigningAuthorityDisplayName"
          ng-model="selectedUser.SigningAuthority"
          ng-options="signingAuthority as signingAuthority.SigningAuthorityDisplayName for signingAuthority in signingAuthorityList track by signingAuthority.SigningAuthoritySystemName"&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>This works perfectly when I'm editing an existing user profile and the <code>selectedUser.SigningAuthority</code> object is populated. The drop down defaults to the value of <code>SigningAuthority</code> as expected. But when I try to add a new user profile and <code>selectedUser.SigingingAuthority</code> is <code>null</code> I want the drop down list to default to a specific value. How do I tell angular to select a specific default value when <code>selectedUser.SigningAuthority</code> is null?</p>