This question already has an answer here:
I occasionally play microstake NLHE on PokerStars, and there I've recently witnessed (what feels like) a suspicious number of "unlikely" deals.
The most recent was in a 6-ring game, in which 1 seat was unoccupied and 1 player was sitting out—so only 4 players dealt. Of those, one folded and the other three went all-in pre-flop. Over their hole cards flip, and all three have KJs! What are the odds of that?
But I've also been seeing KK come up against QQ or AA quite a lot recently (again in 6-ring games): more than I used to see, and more than my gut says should be happening. Again, players go all-in pre-flop.
A cynic might wonder whether the deal is being manipulated to encourage betting (and thereby increase the excitement and/or rake).
How can one measure whether this is within the bounds of normality, or whether something is awry? Does anyone independent actually do this, and what action is taken if something is not right?