Hey,
It is possible to find the best parameter for technical indicator using data science (statistic, ML,…) (for exemple basic parameter for the RSI is 14)?
Yes, it is possible to find the optimal parameter for technical indicator using ML techniques. One of the ways of parameter tuning is using the GridSearch. It lets you select the best parameters from a list of parameter options you provide for your problem.
From the trading perspective, you can read this article on choosing the right technical indicator parameters.