Tharsis in random map selection

[marcopar]

After many plays I'm starting to have the feeling that Tharsis never comes up in random map selection... Coincidence or I'm missing something?

[Yahyra]

I think I have gotten Tharsis in random map... but I cannot recall nor prove it.

[ZWS]

We had it 2 days ago

[charliec247]

My last tournament game on random map was Tharsis

[Peach 2d]

For what it's worth: I have 4 tourney games on with random map settings. Two on Tharsis, one of Vastitas, one on Hellas. Elysium is missing. Tharsis is grossly overrepresented

What you describe sounds like the clustering illusion. A particular map may show up disproportionately often in a small sample size, or another one remains absent, and that may give you the idea that this is not random at all: something fishy seems to be going on. In small sample sizes of random events, however, you should statistically expect skewed "clustering" to happen relatively often. Once you go for really large samples (hundreds, or thousands, and theoretically: go to infinity), you will approach the expected value of 25% for each map . Within that large selection, you'll see instances of the same map appearing several times in a row, a particular map not appearing at all for a long time, and so on. Your experience is an example of that.

Unless the "random maps" setting is not truly random. I'll have to admit that I have no idea how it's been programmed here on BGA.

[Il Commendatore]

For those who fancy seeing a mathemetician explain related stuff in a documentary, this video is just the thing. In this case, it's about random numbers:
https://youtu.be/sKiz5smpvE8?si=pKoYDlJb3knsJsUt&t=1551