Game Center GOF2 HD Leaderboards ranking, how it works?

[Orac7]

Hey Guy's, just wondering if anyone out there knows how the Game Center leaderboards ranking works for GOF2 HD?

You've got subsectional breakdown of indivdualized characteristical gaming stats and ranking respectively ie

1. Kills
2. Missions completed
3. Character level
4. Good produced
5. Ores mined
6. Cores mined
7. Cargo salvaged
8. Credits

Is the overall rank calculated as an average or do some have more weight than others?

Is there some special formula that one can use to calculate/predict one's overall ranking?

Incidentally, does anyone know how the "3. Character level" aspect is calculated?

Ranking is worked mathematical statistics, so not sure why it's a mystery or maybe I'm just unaware of information out there about it as I'm relatively new to gaming.

Any info would be appreciated.

Thanks..