A new factor evaluating the performance (to be added in the player's statistics)

[Leo]

Ok.
That player is 10-0-0
Let's say  I am 0-0-10. I did my part as a supporter. But the formula punishes me for that I didn't steal kills from the carry hero.

In total the assists are much more than the kills in a game.  In Part 1 and the up-part(don't know the math term in english) in Part 2 already Assists are counted with the very weight as Kills. (Doing 10 assists is easier rather than doing 10 kills). 

http://playdota.eu/stats/game/2142545/rd-pdeu-1700
Undead: 6 kills and 30 assists. Did you play good? Yes. Will the formula punish him for not getting more kills and less assists? Yes. Is it fair? No.

Part 2 can be simply the implemented (K+A)/ND - the N there is to match your ranges( every part to be ~1). A good possible approximation would be N=4 (for every death of yours to have helped for 4 enemy kills)