For these concerned with variance. ..
There is only one real sorce of roulette results, their dispersion, distrebution and variance of their respective frequencies. IT'S BALL JUMPS.
So one studing particular ball/ wheel case should focus on ball jumps. Need to look what ball does and when ( conditions). In " when" ( conditions) part you may include all variables of interest.
There are simple guidelines to follow: determine wich conditions ball jump more/ less/ stop... ets.
Stupid to follow numbers, for example, when ball don't jump much... or stupid to follow distances when ball jump without clear defined pattern....
I wanna stress the fact that such study is essential for anyone willing to play this game , be it AP or not. Even if you play systems, it's beneficial to know when these have higher chance to produce positive result, right?
A short idea about numbers themselves. .. they do not exist without distances. Numbers themselves are located at the end of the spin, before the number come ball jump, before ball jump come diamond hit, ball rotations, type of throw, dealer hand..... it's a lot of things happen before number is desided. It's a whole bunch of information that can be correlated with final numbers. To put it simple, it's in front of our eyes and should be used to our benefit as a player.