Has balance of 4 to 2 player games played on the servers changed?


#1

It seems to me that until recently (e.g. until the last 12 hours or so) the was roughly a 50:50 split between 2 and 4 player games. Now it seems more like 20:80.

Has this actually changed? And if so it it on purpose?

This has caused the rating of my bot to climb, BTW, as it seems to be better at 4 player games than it is at two player games at the moment.

Cheers, Tim.


#2

OK, I recently posted another version of my bot and now it’s back to about a 50:50 ratio between two and four player games.

I analysed the game results list of my bot for the last few hundred games.

For the 65 games my new bot has played so far, the numbers are:
32 two player games (50%)
33 four player games (50%)

for the previous 316 games my v26 bot played:
76 two player games (24%)
240 four player games (76%)

and for the 199 games prior to that:
87 two player games (44%)
112 four player games (56%)

Wierd huh?

Is anyone else seeing this kind of behaviour in the games their bot is playing?


#3

This is expected, though unintuitive. Here’s how it works.

For most of the games, halite picks a newly uploaded bot. It then flips an even coin to decide if the game will be a two player or a four player game.

So when your bot is new, you see a roughly 50/50 split.

However, as your bot fades out of newness, you are less and less often the seeding player. Now your games come from others seeding and you being picked as an opponent.

A two player game needs one opponent, while a four player game needs three opponents. Thus with an old bot, you end up with 25%/75% split in favor four player games - which is exactly what you are seeing.


#4

Ah, that explains it, thanks!

My v26 bot was probably the first one where I’ve let it play enough games for me to observe this behaviour.


#5

Why have 2 player games at all then or not have them as a separate tournament?


#6

The metagame in a two player game is potentially very different. A two player game is closer to a zero sum game - if you can spend 1000 to hurt your enemy 1100 halite, that’s a net positive. In a four player game, cooperation and non-agression can help. Mutual losses let the other players get ahead.

And remember, the server is still playing about 50%/50% of each kind. And two player games take half the CPU resources that a four player game does.