Many traders use technical analysis in trading their every day.
They believe in it despite the fact that technical analysis is highly subjective.
Technical analysis that cannot be quantified is a useless illusion that fools many traders.
Only quantitative technical analysis works where we use statistical methods to quantify everything.
Stochastic calculus is being heavily used in quantitative finance.
I have written this blog post in which I explain how we can use random variables and expectation in trading.
We should treat the buy/sell signals generated through technical analysis as random variables.
Elliott Waves, Dow Theory and stuff like that are stories with no predictive power.
What you should do is use machine learning and build trading models that can be rigorously evaluated.
Any trading strategy that cannot be quantified is subjective and just a waste of time.
Once we have random variables we can then study the probability distribution and make proper inferences from it.
