DislikedBefore discussing the randomness of the price, one need to have a clear understanding of the market (and in no way i am claiming that i clearly understand the markets). my simple mind tells me that financial market is a complex system with hundreds of components (instruments, mechanisms) interacting with each other every single moment and adapting to the outcomes of these interactions. Just to give a few example for financial market components: capital markets (stock markets, bond markets), commodity markets, money markets, derivatives markets,...Ignored
Regarding backtesting,theoretically it is possible to predict the future by backtesting the past datas simply because patterns('habits') repeat again and again and will be repeating again and again in future also.The only problem is in the complexity in devising an computer algorithm that translates the successful manual trade strategies.
-CKB