“We are making some improvements to matchmaking to put players with similar play styles together. For example, players who repeatedly abandon games before they begin, or intentionally throw the match. We want to make sure these sorts of players can more easily find each other, to increase everybody’s enjoyment of the game.”
However, debuggers have found clues in Dota 2’s code that seems to confirm Valve examines player activity during the matchmaking process. Every player has a “behavior score” that gets bumped up by positive activity–commends, not abandoning, high KDA–and knocked down for negative activity–reports, abandons, KDA’s that suggest intentional feeding.