more likely hfts or anyone would be on the other side of an ISO taking advantage of a price swing to buy cheap or sell dear. at least thats how it was in '08 when this was popular
it might be easier to think of of bookmakers set odds
https://betting.betfair.com/the-art-of-bookmaking.html
http://www.soccerwidow.com/football-gambling/betting-knowledge/betting-advice/bookmakers/how-do-bookmakers-tick/...
You cannot get on board. You have to ask compliance if the trade you are about to make is OK. Then they get back to you ... after the train has left the station
use an option model/calculator and plug in the numbers
assuming you're referring to calls then the stock could go down and the option not move if implied volatility goes up. volume is irrelevant.
you cannot day trade if you work for a bank, broker dealer, hedge fund, legitimate prop firm. You need to disclose what you plan to buy (no shorts), they approve it, and you have to hold for +30 days. There's a reason why all these firms have compliance personnel now.
one good thing about being a "hired" trader is that you can leverage off the firm's knowledge, infrastructure, ... Then if you leave that position and try to trade on your own you're just like everyone else and most likely lose.
here's using a pyton pandas dataframe
def beta (dfpctchg,seriespctchg):
""" dfpctchg : 2 column pctchange dataframe
seriespctchg : series of second column
In [32]: p.tail()
Out[32]:
Adj_Close Settle
Date
2014-12-09 0.002320...