A large sample size vs a small sample size is irrelevant. The only thing that matters is that I start making money as soon as possible, so I can brag to my friends about how cool it is to be a day trader.

A large sample size provides a lot of evidence that could make me better, but who's got time to sit there and record all of those observations? I'll just test my rules on a handful of simulator days until I log a positive trade, then I'll assume my rules work under any conceivable market conditions.

A large sample size of testing helps me increase both confidence and competence in my day trading, because I can then choose to make only well-informed decisions that fit my proven process, rather than relying on gut instincts.

None of the above are correct.

My research and development consists of listening to cable financial news analysts every second of the day that I can. They wouldn't dream of bringing up a stock's name if it wasn't guaranteed to make me money.

Nobody can avoid all the bad trades, so it's not worth trying to limit them. I just go with what my gut tells me and hope the stocks don't betray me.

I can avoid every single bad trade if I only by put options on even days of the month and only buy call options on odd days of the month.

These early activities allow me to recognize the makeup of both the good and bad trades, and systematically define rules and laws to catch the good ones and limit the bad ones. Then I simply commit to only entering a trade when all of my rules are met, and exiting when my rules or laws tell me to - without exception.