Hey all, I posted this on reddit but it went nowhere and I thought I should post it here to get a little more visibility from the devs.

Recently I was thinking about how ranked MMR is presented and I feel like

they blew the MMR implementation very badly. It's not just extremely barebone, but works actively to make you feel bad about playing ranked matches in my opinion. Please note that

**this isn't a critique on their MMR formula**, which I know nothing about but seems quite credible. This is a critique on the way ranked play was implemented, where you get two simple MMR numbers that are updated after each match.

I'm 100% behind Dota having a ranked system. We all strive to improve and it takes away the pressure from unranked games. A ranked system supposedly gives you the incentive to actively improve your skills and get better. Currently, Valve gives you the exact number used by their formula, along with its update after every match. This is in my opinion bad for several reasons:

**Humans have loss aversion.**
This means that

you are way more bummed out by a 25 points loss on your MMR than by a 25 point gain. Loss aversion isn't so much of a problem with unranked Dota because every match is different,

so sometimes a close loss is satisfying while a stomp where you barely use your core items doesn't feel as great. However, with a numerical measure of your gains and losses, there's simply no way out of loss aversion. This ties very closely to the second problem:

**Humans are very bad at recognizing variance.**
The MMR climb is essentially a

random walk where the average drift depends on your skill. On every Dota game you have a certain probability of winning and your skill can improve (or decrease) that probability.

But except on the most lopsided matches, no team has a 100% chance of winning a match. What this means is that you're going to both lose and win frequently and unless you are seriously underranked (or overranked) your improvement can only be reflected over a reasonable number of samples.

But we all know that, right? Why bring it up? Because humans don't know how to recognize that variance. We are also specially bad at recognizing streaks (either wins or losses) as part of random chance. This means that you will win a lot, feel pretty confident, then lose a lot and this will be just part of the random walk. But the losing streak feels way worse and we get stressed in the process. Then the next match

*has* to take us out of the pit we just got ourselves into. I mean, if I lose another game I'll go below 3k and this will be awful. I'm sure the next match won't be stressful at all.

This is obviously not exclusive to Dota. This is a problem for Poker players, whose livelihood depends on the state of their bankroll and have to deal with losing streaks, knowing that if they lose further they might not have enough money to play on the high stakes tables and then have to work way more to themselves out of the pit and back in their old financial situation. The same goes for anyone trading their own money in the financial market.

But by giving an exact, precise number to MMR, Valve has placed this heavy burden on accepting variance on ranked players. This is compounded by the fact that most of us plateau and

ranked gives you feelings of loss where there shouldn't be any (because

you are not actually getting worse or better, just riding the variance). And this is specially unnecessary because...

**Only the first two digits of the MMR matter.**
Consider this thought experiment: suppose Na'vi and Alliance are equally skilled at 7000 team MMR and this is their "true" MMR, perfectly reflecting their abilities. Again, this is not a critique of the MMR method, but it's important to understand its limitations.

They play a game. One of them is going to gain 25 points and the other will lose 25 points. So right off the bat the MMR system has a 25 point uncertainty that in no way reflects your skill. Furthermore, Na'vi has 25% chance of losing twice in a row and then will end up with a 50 point delta from their real MMR and Alliance will end up 50 points better. And a variance of this size will happen 50% of the time they play two matches in a row (because it could swing both ways). Only on the other 50% of the time will they end 1-1 and their MMR will end up even after two games.

At some point, of course, if Na'vi loses too many matches in a row you have to discard the hypotheses that they are of same skill that of Alliance. But this is somewhat beyond 2 losses in a row and therefore beyond a 50 point difference. The loss and gain of MMR decreases with the difference (ie, Na'vi won't lose 250 points on a 10 loss streak), but the principle holds for small variations. It hardly matters if your MMR is 3573 or 3548 yet right now as presented everyone will sweat over the difference.

Valve would already have done much better, for example, if they simply rounded your MMR to the lowest hundred, so that you jump from 2600 to 2700, from 5100 to 5000, etc and MMR variantions inside a hundreth (sp?) are hidden. Way less variance, more average tendencies. Of course, losing 100 MMR sucks too, but this would be happen way less frequently precisely because it would better reflect the average MMR. Not that I think this is the best implementation, but it would already be an improvement over the current system.

I will stop now because the post is lengthy already and

these are in my opinion the major problems with the current MMR system. Note that this doesn't touch the fact that the

ranked system is extremely simple right now (no ladder, no graphs showing your progression, no idea of where you are among the Dota community, etc). But even

this simple implementation is bad at motivating players to play and try to improve their MMR.

What are your thoughts on that? Do you feel like the current MMR gives good incentives to keep playing?

**tl;dr:** A single number gives you more ladder anxiety,

bums you out everytime you lose and is not a good representation of your skill and skill improvement.