By "swingy" I am referring to the players' hand equities varying during the course of the play of the hand. I am not referring to money, chips, bankroll, etc. (though of course the two are related).

Just from a mathematical and probability perspective, what poker variants are the most and least swingy. Inherent to the game itself.

Way back when, an early poker variant dealt everyone five cards and then there was a round of betting. And then showdown. Best hand on the initial deal won the hand, of course, since there are no additional cards dealt, no draws, etc. So this is the least swingy game possible.

In Omaha, hand equities are fairly narrow preflop. But then as the flop, turn, and river are dealt, individual hand equities can look like a roller coaster. I would consider Omaha very swingy.

HoldEm is similar but not to the same degree for obvious reasons.

Also, I suppose that in games that you can get counterfeit such as O8, your equity can swing wildly. As opposed to Stud Hi, say. Razz is also swingy not because of counterfeiting but each street can flip the equities (one player catches good and another player catches bad).

Draw games can be swingy too. Single draw vs. Triple draw. I wonder if high games are more or less swingy than low games (or would they be equally swingy).

Has anybody seen anything on this topic? Can anybody think of what a good metric would be to define a game's "swingyness"?

standard dev?

doh! I just reread OP. I must've breezed over the first paragraph.

What causes hands equities to change intra-hand in some games more than others?

It must have something to do with the average starting hand strength relative to average finishing hand strength. And the amount of this relative change for each betting round along the way. That's driven by possibilities/combinations to improve. More possibilities makes for more distance between hand strengths from one betting round to the next.

maybe something like equity of a good hand range pre/postflop vs 100% (random hand)? the game where that equity is lower will have bigger swings.

here's a comparison between plo and nlhe that way

preflop:


on some random flop: