What do the dots mean?

[3c1s]

I've noticed dots by names in the game. I've seen green, pink, blue - some are filled in some are empty. What do these mean and what do the colors signify?

[Sugita Yuuichi]

Karma is represented by 1 to 5 dots (from worst to best) located to the right of a player' banner. The number located below the Karma dots is that player's Ranking Score.
As a new player, you start with 50 Karma points (2.5 dots). When you play an online game to its completion, you earn 1 additional Karma point (up to a maximum of 100). When you abandon a game in mid-play, before its normal completion, you lose 5 points.