The Headis World Ranking is compiled by the last 15 World Cup Tournaments. The tournaments get a ratin (stars), The points each player reaches at the tournamen are multiplied with the rating. The Winner of the Headis World Championship (only 5 star tournament) is getting 200 points in total for the Headis Ranking (40 points for the 1st place multiplied with the 5 stars).
The Headis Tournaments are rated between 1 and 5 stars. There are half stars as well. If two players have the same count of points the one that has played less tournaments.