Categorization of Notifications for social sites in SharePoint 2013

Hi,

We have been trying to do categorization of notifications using following parameters:-

• People I am following.
• Documents and Sites
• Tags

We have succeeded in doing the People I am following and Tags part of it. Also we are able to fetch notification of Documents and Sites I am following together.Now we are stucked in separation of Documents and Sites. We have explored the svc - /_api/social.feed/my/News of mysite in SharePoint 2013  , but we did not find any differentiating attributes between both of them.

Please suggest any approach to achieve this.

Thanks in advance.