How is it determined whether you get the Daily Super Jackpot in Halo Reach?

How is it determined whether you get the Daily Super Jackpot in Halo Reach? im just wondering what determines whether you get it or not. for example is it your points you scored in the game or whether you win, or could it be completely random. please only answer if you are certain or have a very good idea. also what tips do you have for someone trying to get it.