Is something that I have been avoiding this week, by moving temporarily down to $20NL, but I got to thinking about it whilst commenting on Ricci's blog this morning (http://riccinas.blogspot.com/).
Having looked closely at both $20NL and $50NL on Prima this month, I would say that the main difference is that there are more aggressive players on $50NL.
This is to be expected, of course, but it strikes me that it does very dramatically increase the variance that you will experience.
Apologies for the extremely over-simplified maths that follows(!), but as the stakes are 2.5x higher, and there are perhaps twice as many aggro players, I think that the $50NL game could easily result in swings that are 5x greater (in pure dollar terms) than at $20NL.
I think it is possible to imagine that people are slightly less likely to push all-in at $50NL than at $25NL, simply because it is more money to risk, but I think that this is very significantly more than offset by the fact that people are willing to 3bet and 4bet either very light, or with complete air.
I know that this is a grossly simplistic line of thought, but I am thinking that a session "running good" at $20NL might result in a win of say $20 in 200 hands, and a session "running bad" at $20NL might result in a loss of say $15.
By applying the 5x multiplier, this could mean that running good at $50NL I could win $100 in 200 hands, whilst I could expect to lose $75 in 200 hands when running bad. Does this make sense?
Also, when considering $100NL, I assume that this game is a further degree more aggressive, and so could result in even more variance?
I am not sure where this line of thought is leading, except to reinforce the need to be properly bankrolled for a given level, and to ensure that one sets stop-losses when moving up, to make sure that the variance doesn't consume you whilst you are finding your feet at the higher stakes.
So, when moving up, it is perfectly possible to imagine that you string 4 or 5 sessions of "running bad" together, add in a a bit of tilt at your "bad luck", and before you know it, you have lost 7 or 8 buyins or nearly half your bankroll (assuming that you started with the 20x minimum for the new level).
Food for thought...