Can somebody please explain me dodging system in ranked

So I never used to do that, but 1 recent occassion a bit shocked me. So I dodged lobby game, I got 1.5 min penaly and -3 lp. Next lobby I also dodged a got -10 lp ?? It is almost like losing a game. Aside from it I just want to get some basic knowledge of that.

1. So how does this lp deduction work with dodging lobbies ?
2. What happens if the game hasn't started yet, but I close loading screen and never connect. How much lp do I lose ? (aka remake because of me)