Ask HN: Interaction score for HN posts

Besides score and points if we want to add one more attribute for HN posts which represents the interaction that happens on the post, how should it be formed?

I am interested in this data as some posts will get more points but if you comment on it no one is going to respond to you. The interaction in that post is very bad. Some of these posts are there even in the front page. Note: if OP interacts that post seems to be more engaging.