By this I mean I heard an old piece of "wisdom" years ago that said if a stock breaks 100 it will likely go to 110. Has anyone done any testing on this? If so, what did you find as far as regularity, sector importance, etc. etc.?
How creative: You've just read Reminiscences of a Stock Operator... What you need to take into account is that stocks back then (in the 1920s) were: a) less liquid, and b) spreads were much, much wider. Those two elements made for more volatility, though theoretically it would balance out since one could not get into size as easily as today.
Forgive me CT as I've never (gulp, dare I say) read that "bible" on trading. I've seen the book mentioned, you can probably guess how many times! Yet, I've never gotten around to reading it. I was wondering if anyone had done any back testing on that info. Thanks for your insight as to the market conditions when that 100-110 statement was made.
I remember examining lots of stock charts looking for price behavior similar to what you describe. I do not recall finding enough consistent and reliable examples specifically at $ 100 / share to consider testing. I do not recall seeing enough consistently profitable examples at $ 200 or $ 300 / share, or even $ 10 increments to consider a formal back test. I recall reading on the web about a similar trading concept involving "price magnets". If I understand the concept correctly when price moves above say $ 50.21 / share then price is likely to change to $ 51 / share before trading at $ 50.00 / share. The idea is that price is usually attracted to the next whole number, or perhaps half point values. The price magnet idea might be useful for short term trading.