SteveHopwood » Wed Oct 31, 2018 3:42 pm wrote:V 1u is in post 1, with the hedging thingy fixed and FLAT signal hedging removed.
Thomas sent me this explanation of the PriceFractions TP and SL option. I have added it to the user guide:
I am used from stocks and options trading to set TPs and SLs in percent of price. For example a TP of 10% means a $20 stock has to move $2, while a $200 stock has to move $20.
This problem is to a smaller degree also existent in Forex. Lets take USDCAD with a price around 1.30 and NZDUSD with a price around 0.65. To achieve a 100 pips TP, NZDUSD would have to move twice as much than USDCAD in relation to the price.
A pip is defined as a change of ±1 at the 5th digit of price. Hence the 10000th (0.0001) fractions. 100 of these fractions equal 100 pips if the price is exactly 1.0.
For USDCAD (@1.30) 100 of these fractions equal 130 pips while for NZDUSD (@0.65) 100 of these fractions equal 65 pips. If we calculate SLs and TPs this way, each pair now has to move the same distance relative to its price.
Thanks for that Thomas - most helpful.

Thanks Steve, that helps me understand it........ even if I don't agree with it.... I don't want to offend anyone here so please all take this post as just my opinion and not a comment on anyone else's.
I just wanted to add my view of how to automate SL and TP calculations and explain why I feel that price fractions isn't for me. When trading stocks, people tend to invest a lump of cash and then measure the performance based on the % change in the value of that cash. They don't care if they have to buy 10 shares with their lump or 1000 shares, it's all the same - it's just a lump sum invested. If price moves up, say 10%, then they might sell or add more. They are focussed on % price moves because that's the way it works.
On forex, the banks work in much the same way. They will invest a % of their cash holding in a particular currency in the hope that it will deliver a % return. They are not bothered about pips but rather the current value of their lump sum invested. However, for the short term trader using leverage, things are very different.
Short term trading is all about probability. We are looking for what is "most likely" to happen in terms of price movement. Our entries and money management are designed to be aligned to what is most "likely" to happen to price. An "edge" is simply a term used to describe the amount your strategy beats the average or random outcome. So when looking for SL's and TP's we should be looking for measures with similar probability of happening. Price moves don't always give us this. (and pip moves definitely don't!)
Take USDCAD and NZDUSD as an example. Their current prices at this time are 1.31017 and 0.67918 resp. A 0.5% move in each would be a price move of 0.006551(USDCAD) and 0.003396(NZDUSD) resp. So this could be used as a TP or SL perhaps? Well, let's look at how "likely" those moves are. Based on a 14 day ATR, these moves would be 95% (USDCAD) and 261%(NZDUSD) of ATR. So for USDCAD to reach its 0.5% price move it would have to move less than it's done on average each day for the last 14 days - so that's quite likely. However, NZDUSD would have to move 2.61 times its average daily price move which is much less likely. So a 0.5% move in price is much more "likely" to happen on USDCAD than NZDUSD and that changes everything when you're betting on probabilities.
If you're trading multiple currencies and you want to take the same "risk" on each, my belief is that you need to risk the same amount of cash on each "event" (SL or TP) that has the same probability of happening. I feel that sized positions and ATR based SL's and TP's are the only way to do this.
Just my opinion....
Bruster