In hold em high, the players show down their hands and the best hand wins.
In hold em 2nd best, of the player's highest hands, the second highest hand wins.
In hold em "true inversion," of the player's highest hands, the lowest wins. (Here's the original version:
Lomaha When playing heads up, 2nd best and true inversion are functionally identical.
Here's a couple of charts of two runs: one of HE high, the other HE second best. Both were 100k iterations for each of the 169 distinct HE hands vs random hands. The first chart the high and 2nd best value for each hand (AA, 23o etc.). The second chart shows the hand distributions from each game, best to worst.
Pretty much what I'd expect. Note that the best high hand (AA) is better than the best 2nd best hand (32o), and the worst 2nd best hand (AA) is worse than the worst high hand (32o). More later.