User blog comment:Sylvandyr/The math behind the Battle Arena/@comment-26845384-20150818024258/@comment-4830404-20150827180236

I just randomly happened to stop by, so I can answer that! For your question about the type scores, I can verify when I get home in a few hours. Basically (as you noticed with the type chart) this blog is angled at describing what the DS dev's code is doing, so I break it down as-is.

Not sure if there was a specific reason for the 4 type advantage to be 3 unless I read their code and they did some weird default values in a silly way. I will check to see if it was bad defaulting on their end or if I made a typo.