&gt; <i>Specifically, we extract users’ email addresses from GHTorrent, look up that email address on the Google+ social network, then, if that user has a profile, extract gender information from these users’ profiles.</i><p>I was curious so I looked up the Google+ API (<a href="https:&#x2F;&#x2F;developers.google.com&#x2F;+&#x2F;web&#x2F;api&#x2F;rest&#x2F;" rel="nofollow">https:&#x2F;&#x2F;developers.google.com&#x2F;+&#x2F;web&#x2F;api&#x2F;rest&#x2F;</a>) and I do not see an &quot;email lookup&quot; endpoint. You can only search for generic information in public profiles. Searching for my own email, which is public in Google+, using that particular endpoint yielded no results.<p>I call shennanigans that <i>1&#x2F;3</i> of the accounts in the dataset had discoverable profiles this way, and they were retrieved in a manner that is acceptable by Google.