Negative karma is given in any post that deserves to get negative karma. However, if someone does karma farming unnecessarily, then action is taken against him. If you get a lot of negative karma together, you can judge in the forum court. If karma farming is attested, the specific karma that it must be known as karma abuser.
I think the forum community is very active here. So to bring good behavior to every community, or good behavior to every user, is the result of positive karma. These should work for testing. By removing the negative karma or positive karma system, only the positive karma system. More positive feedback and negative feedback should be developed. Some users should be given the ability to go to this feedback. The subject is great, but it is suggestive.