Quote from mrfong8:
We all know statistics is a helpful subject for trading, what i hear about mostly are standard deviation and theory of probability.
What other tools can non-mathmatical trader use at their disposal to make their trading more precise and scientific?
I've found the anything beyond the simplest statistics to be meaningless when it comes to trading. The reason is that most statistical techniques have fairly strong assumptions about underlying distribution, which are often very difficult to confirm or measure reliably at all.
I have found that using simple "sanity check", such as positive expectancy, std(trades) not too large relative to the average trade, profit / dd much larger than one over a few years, etc. Those are the sorts of things I'd look at.
Just remember, that the math behind the statistics still produces a result; you have to be careful with how strong conclusions you try to draw from them.