An objective measure of the difference in strength between top programs and top human players in the four most popular forms of chess? Is there an objective measure of the superiority (or otherwise) that the strongest computer programs enjoy over the strongest human players which can be compared across the four main forms of chess, namely western chess, xiang qi (Chinese chess), shogi (Japanese chess), and makruk (Thai chess)? For example, can it be said that on comparable Elo scales the programs have say an x point advantage in western chess, a y point one in Chinese chess, and lag behind in the other two games by z points?
I would have to answer no in my opinion. The four forms of chess are different. Shogi from what I remember is a form of chess where capturing an opponent's piece allows you to, at a time of your choosing, put one of that piece on the board as yours. Now that is a level of tactical complexity that surely gives any engine a huge advantage over any strength of human. I have played a little Xiang Qi and I would say the same; in the 90's when Chinese players played Professional western chess for the first time they were awesome tacticians; Xiang Qi as their previous game being very tactical led to that.