Ok whatever you don't seem to be very forthcoming with corrections....Im nothing if not good at asking questions none of which seem to be worthy of your time... Very superior attitude "As someone" who knows a few things about a few things and always willing to explain when I have a willing ear...
enki74, first, you are embedding your replies in other people's txt... makes it very difficult to understand or read (see post above).
2nd, you are still confusing _cost of trade_ and _price movement_. As someone who actually makes a living trading, and doing so for a great many years, I can tell you that your trading assumptions are wrong, and will lose you money. On the up side, Stephan's bot will protect you from yourself, as it is pretty foolproof (please don't take offense), and will work hard to keep you from making losing trades.
If you want to see the result for yourself, do some manual live trading off your formula. The beauty of math is that numbers do not lie.
Better enki74... thank you for separating your txt from the quoted txt... makes your posts more readable.
I apologize if I have not answered your question, I did try.
Let me try in a different way. You are confusing the fee%/actualcost/movement%/movementactualcost ratios.
The basic flaw in your math is that you are somehow tying the trade amount to the movement/% fee equation. That is simply not correct.
Using round numbers again, suppose BTC is worth $100/ea, & the exchange charges a 0.2% fee for each trade.
Because we know it takes two trades to make a profit, we know we have to double the fee (two trades) to arrive at what our minimum drop/raise will be. In this case, it is 0.4%
This means we can calculate the minimum drop/raise thusly: 100*0.004 = $0.40
You have now calculated the minimum amount the price must move for you to make a trade and _not_ lose money.
Lets make a trade. Lets Trade $1 worth of BTC. If we buy @ $99.60 & sell @ $100 we have traded using the calculated $0.40 minimum, and have lost no money... end result = 0
Lets make another trade. Lets Trade $100 worth of BTC. If we buy @ $99.60 & sell @ $100 we have traded using the calculated $0.40 minimum, and have lost no money... end result = 0
Lets make a final trade. Lets Trade $0.000001 worth of BTC. If we buy @ $99.60 & sell @ $100 we have traded using the calculated $0.40 minimum, and have lost no money... end result = 0
Why? Because (100-99.60)-(100*0.004)=0 (tradeamount[sell]-(tradeamount[buy])-(tradeamount*fee)
and (1-0.60)-(1*0.004)=0
and of course (0.000001-0.0006)-(0.000001*0.004)=0
This means that there is no trade amount that will affect the actual drop amount needed to make a profit.
Honestly sir, I am at a loss for how I could be more "forthcoming". I grant that maybe I am not explaining it right, so I invite you to test in on your own. Use small amounts tho, because math is a cruel, unforgiving master. If you get it wrong, she will exact her price on you.
Sean