How to use Neovis.js to show my relationship

Here i want to use Neovis.js to show my points and relationships.And i know the use of "caption" is to select the propety that i want to show.However i can't use it, if i write:

labels: {
      "Character":{
             "caption": "name",
             "size" : "pagerank",
             "community": "community"
        }

and i get nothing except a circle, just like: