You appear to be shadowbanned. I vouched for this comment so that I could reply to it.
If my expectation for a stock is something other than the current value, I am claiming that I can predict the price. It doesn't matter whether my predictions are accurate or not, it's a statement about my beliefs.
A martingale model is consistent with believing that I can't predict the stock price. A non-martingale model implies believing that I can predict the stock price.
If my expectation for a stock is something other than the current value, I am claiming that I can predict the price. It doesn't matter whether my predictions are accurate or not, it's a statement about my beliefs.
A martingale model is consistent with believing that I can't predict the stock price. A non-martingale model implies believing that I can predict the stock price.