[Biggs]

I think it takes your skill points from servers on the official hlstats server list or "trusted gameservers" and averages them out. I could be wrong though as that is just an assumption. It could incorporate the kills, deaths, and kpd in with the average skills points too.
Also I've noticed that the globalstats doesn't have detailed stats, just general stats.

official server list http://www.hlstatsx.com/masterserver?eng...masterlist