Server update today (14/1-2015)

[Sheeo]

The server is being updated today to fix an issue with ladder map selection. You should no longer be getting completely random ladder maps.

The choice of ladder map given two players works as follows:

Each player selects 15 or more maps using the "Select maps" button in the "Find games" tab.

When two players are matched in ladder, the system either chooses maps from one of the players' selected map pool, or the most popularly selected ladder maps. Each of these cases have 1/3 probability.

When a player has less than 15 maps selected, their pool is filled with popular ladder maps.


This is the same system we had in place before, but now players with less than 15 maps selected will not get completely random ladder maps added into the pool.


-The Council

[ZLO_RD]

So there was a bug that caused people to play on random maps?
So no any improvement besides that?

Well I am ok with that, and I hope others are ok too...

But there is always be that guy that choose 15 most broken/imba/unusual/frustrating, so everyone that plays him will think that they always (33% of the time) get random stupid maps.

[Sheeo]

So there was a bug that caused people to play on random maps?
So no any improvement besides that?

That's right, yes.

But there is always be that guy that choose 15 most broken/imba/unusual/frustrating, so everyone that plays him will think that they always (33% of the time) get random stupid maps.

Broken and imbalanced maps aren't meant to be in the ladder pool, though, I believe the most obvious subjects have been removed, but if there are more we should get those removed -- do you have any specific maps that are broken and/or imbalanced?

Whether a map is frustrating or not is a subjective matter.

[Sir Prize]

This will potentially be our latest ladder map pool threadnaught so I'm just going to get in on the ground floor and say - if two people have the same maps in their pool when they're matched for a 1v1, they really should be getting those maps, with possible very rare exceptions.

If you get sick of playing a map cos you always get the same dude and the same map, change your selection. I would be very surprised if you're not also extremely rare and the ladder system shouldn't really be altered to meet your needs when you could just change your maps up a bit.

[Vee]

Speed2/doom found a broken map: https://www.youtube.com/watch?v=TVwAqHJ1YJg#t=1660

[Sheeo]

This will potentially be our latest ladder map pool threadnaught so I'm just going to get in on the ground floor and say - if two people have the same maps in their pool when they're matched for a 1v1, they really should be getting those maps, with possible very rare exceptions.

If you get sick of playing a map cos you always get the same dude and the same map, change your selection. I would be very surprised if you're not also extremely rare and the ladder system shouldn't really be altered to meet your needs when you could just change your maps up a bit.

They will. To specify the algorithm more rigidly, it works as follows:

The selection pool starts out as the intersection of selected maps for player1 and player2

If there are less than 15 maps in this pool, either maps from player1, player2 or 'popular' (With a 1/3 probability of either) are added until there are 15.

The map chosen is a uniformly random selection from this final pool of 15 maps.

[Lionhardt]

But what is the motivation for this algorithm?

To me it would make way more sense like this:

This requires a new features though...


chooseFrom is the set of maps which the algorithm finally chooses the map from


1) If the intersection is not empty: uniform prob distribution over all members of intersection* (chooseFrom = intersection)
2) if intersection is empty select random map that is not in either of both players map selection with prob distribution proportional to normalized selection count of map (chooseFrom = all maps not in either player's selection)
3) prompt both players with selected map.
4) if players do not both agree on that map pick new map as in 2)


* Keep track of how many times these players have played in x time together (cntMatches), per time they have played together in period x increase chance of picking a random map that is not in either of both players map selection rather than one the two might have already played, as it is in both of their selected maps.** (chooseFrom = intersection + new random maps) (When selecting a random map go to 3)

** if the set of maps that are not in either player's selected maps is smaller than cntMatches add random selection of both players selected maps to maps to chooseFrom. (chooseFrom + k maps from player1 selcetion + k maps from player2 selection)

[Sir Prize]

Thanks Sheeo, that makes much more sense . I'm a bit too tired to be sure but I think I also like the of selecting a map prior to starting too.

[Sheeo]

3) prompt both players with selected map.
4) if players do not both agree on that map pick new map as in 2)

And what happens when a player has declined all the maps not in his selection?

While I like the idea of a single 'veto' (it's better than just quitting the game, yeah?), allowing players to just straight up decline all maps proposed is a bad idea in my opinion.

[speed2]

Speed2/doom found a broken map: https://www.youtube.com/watch?v=TVwAqHJ1YJg#t=1660

yeah! at least someone is paying attention to my casts I totally forgot about it