1. A method comprising: on a social networking service: receiving a first connection invitation from a first member of the social networking service; receiving a second connection invitation from a second member of the social networking service, the first and second connection invitations expressing a desire by the first and second members, respectively, to connect to a subject member of the social networking service; determining a first relevance score for the first member, using one or more computer processors, based upon a first plurality of observed signals, the relevance score indicating a likelihood that the subject member knows the first member; determining a second relevance score for the second member, using the one or more computer processors, based upon a second plurality of observed signals, the second relevance score indicating a likelihood that the subject member knows the second member; and sending a notification to the subject member of the first and second connection invitations, the notification ordered based upon the first and second respective relevance scores of the first and second members.