Sounds like gambling. Are we just making bets and gambling?
If we consider the staking mechanism and the earns and burns solely from the user point-of-view as a risk vs reward math problem, then yes, it fits into that framework. But that's a unnecessarily disingenuous label to put on it, because the same basic equation applies to so many other things we wouldn't dismiss as "mere gambling". Stock market investment for one! Or any kind of investment like buying real estate, starting a business, even things like getting married, etc etc. No risk, no reward is a basic truism everywhere in life. Also, in true gambling-type gambling, there is a "house" hoping for you to lose -- someone that will gain by your loss. Not so here. Everybody wants you to win! Staking at Numerai is about establishing that trust relationship as I mentioned, but the amount you stake is also a indicator of the confidence you have in your predictions -- the more you stake, the more weight your signal is given in the metamodel that determines the trading decisions for the hedge fund. In fact, from what we understand from the team, stake value is actually the only thing that they use to determine how much weight to give to a user model in the metamodel ensemble. (You'll often hear the longer term "stake-weighted metamodel" used, because that's how it is created.)