Calculating trading strategy's future profit
&
minimum R/R ratio calculation

You must have heard very often option seller say that they have edge over option buyers because if market goes either sideways or in their direction then they are going to make money 66% of the time.

But, I would define market edge differently. We are here in stock market to make money. So, edge is if your system is able to produce more alpha then other traders. In simple terms system gives you more profit than other. And mathematically option seller donot or cannot have edge over option buyer. Because, if option seller have high probability but they have low reward:risk ratio and similarly, option buyer have low probability but have high R:R ratio.

If we look at trading system as a whole, then it consists of
1. trading system
2. risk management
3. psychology

So, what happens is that discretionary option seller are able to follow their system better because of high probability. And they have psychological edge over option buyer.

One more thing is that, it is entirely possible to create a complete system regardless of option buying or selling that we can create decent probability with good r:r ratio. So, donot follow inherent thinking but try to innovate/create strategies based on your temperament(psychology), capital, time and risk tolerance.

Profitability = no. of trades x risk per trade x (reward:risk ratio x win % - loss%)