Share value questions

So I see there are different valued shares

For Example (from beeeeer.org)
7=0.00143 8=0.0157 9=0.1908 10=0.2101 X=0.2149

My question is, because I’ve found a lot of 7-CH shares, how do I find the 8’s, 9’s, and 10’s? Does it depend on my Prime rate? How long I’ve been mining? Or is it solely dependent on luck? Is it the same for finding blocks?

Directly with beeeeer you don’t have to care about finding a block, you get payed for your shares, indipendently if the pool has found a block!

finding longer chain is rare, an approximation is: if you find a n-long chain in X minutes, you will find a (n+1)-long chain in 11X minutes!

Anyway long chain is also related to luck since is probabilistic!

So if I leave my miner running for say two weeks straight as opposed to shutting down the miner and starting it back up every once and a while, I would have a better chance of finding long chains?