MMR gains/loss seem random...

I lost 87 MMR rating for this game???

Why?

i can understand if i lose in my own elo i'd lose a lot of mmr...

But for most of their team to be one whole division higher, and one player 2 divisions higher... why would i lose so much mmr for that?

Then 2 games later i gain 13 MMR rating for winning a game where the teams are reasonably balanced.

Prior to the 2 games i lost, i won a game and my mmr went down... ?

http://na.op.gg/summoner/userName=HellawhiteIII

What???

[sg-lux-2]