it really depends on the stats.
1 what lvl you and your team is
2 what lvl the opponents are
3 companion lvls and promotions
4 health and stats
5 your class and your class epics + epics from other classes
6 same as 5 but for other team
7 gear and how good you/teammates/ opponents are at pvp
8 wither im in it or not is a big part, (i must admit i prefer to run in and die than have to keep on worrying about my health, it doesnt matter anyway im terrible at pvp.) i do however land as many epics as i can before i die
9 a bunch of other little things

-jack nightgale lvl 45