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Note : I DO NOT expect to make a 2M profit on 100k in 5 years.
If by greatest number you mean active open positions then that proposition is just out and out wrong. There are so many system factors that you need to take into account before making that statement. For example, a system with a low % of winners will, in general, NOT benefit from a large number of open positions, but a system with a higher % of winners may well benefit from having exposure to a larger number of open positions. Unless you really understand several key properties of your system you cannot make blanket statements like that.That is what you want: you want to expose the greatest number possible to your edge.
jog on
duc
I often think about this statement @Skate and while I think there is a great deal of merit in it I prefer to think that backtesting (the way I do it) is only a means for giving me a level of confidence that my systems have a good chance of making a profit in the future, but there is absolutely no way I will look at backtesting results and say over the next X period of time I should expect a CAGR of Y%...to do so is naïve at best.Backtesting means JACK
@qldfrog, well stated - without getting into another exchange, I want to re-stated that (IMHO), Amibroker backtest results mean "Jack" & hold little interest in assessing the true performance of a strategy. Live trading is the "true measure" as it confirms if your "trading plan" is solid.
Skate
If by greatest number you mean active open positions then that proposition is just out and out wrong. There are so many system factors that you need to take into account before making that statement. For example, a system with a low % of winners will, in general, NOT benefit from a large number of open positions, but a system with a higher % of winners may well benefit from having exposure to a larger number of open positions. Unless you really understand several key properties of your system you cannot make blanket statements like that.
Thanks @peter2 and @MovingAverage , I will follow MA suggestions to try to debug this , I feel better not being alone thinking something is not right.So counter intuitive.Will keep you posted@Skate Thank-you.
@qldfrog , regarding your post with the MC results of the 11pos vs 40 pos.
The completely different equity curves indicate to me that there is a significant error in your system code. It will most likely be in the position sizing code (# trades, # shares).
Other aspects that may influence your observation that 11 pos is better than 20+ positions.
- position score,
- market cap, sector preferencing
- influence of an index filter (small caps don't move the index)
I agree with @MovingAverage 's suggestion of using equal size positions throughout the testing period.
Pos size compounding will make the later results influence the P&L more than the early results.
You may wish to put both of us on ignore while we debate this issue ?I'm thinking
This post will make for an exciting educational exchange. @ducati916 responded to a previous post in "general, concise terms". I'm sure the Duc will respond with an expanded explanation.
Skate.
Debating the merits of an alternative view is how we learnYou may wish to put both of us on ignore while we debate this issue ?
just checked the code : pretty simple and I believe right:@Skate Thank-you.
@qldfrog , regarding your post with the MC results of the 11pos vs 40 pos.
The completely different equity curves indicate to me that there is a significant error in your system code. It will most likely be in the position sizing code (# trades, # shares).
Other aspects that may influence your observation that 11 pos is better than 20+ positions.
- position score,
- market cap, sector preferencing
- influence of an index filter (small caps don't move the index)
I agree with @MovingAverage 's suggestion of using equal size positions throughout the testing period.
Pos size compounding will make the later results influence the P&L more than the early results.
If by greatest number you mean active open positions then that proposition is just out and out wrong. There are so many system factors that you need to take into account before making that statement. For example, a system with a low % of winners will, in general, NOT benefit from a large number of open positions, but a system with a higher % of winners may well benefit from having exposure to a larger number of open positions. Unless you really understand several key properties of your system you cannot make blanket statements like that.
We have talked here and else where a lot about the number of positions in a system
I usually target 20 or so for risk management purpose.
Played a bit yesterday with backtesting this number of max positions and in my systems at least, daily and weekly:
I consistently got much better results with lower max number of positions.
For MA : along 2000+ trades so definitively consistent and statistically relevant
Thanks for stating the so obvious which often stares in my face, yet get ignored.@qldfrog Thanks for the extra work. I hope you got something from it.
I don't use AB and those results require lots more explanation before I could make any clear decisions about the trading system and the optimum number of positions for that system.
The only value in that chart that tells me anything about the system is the W% which is remarkably constant during the increasing number of trades (34%). In order for this system to be profitable the AW/AL must be >2. To get an edge (expectancy) that I'd be comfortable with, the AW/AL would have to be >2.8. Include brokerage and some slippage the AW/AL would have to be >3.
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I totally agree with @ducati916 last two posts (low numbers, edge). Like him, I'm going to jog on and maybe add to my open VIAC position.
To address this, we will have to start with an assumption.
Which is: that the system in question (A) does possess an edge; and
That a random system (B) (no edge) is compared against it.
If the system, A, that has a true edge is exposed to a low number of trades, the results could be (a) better than B, (b) worse than B, (c) equivalent to B.
The higher the number of trades taken, then the more system A will start to demonstrate its edge as compared to B.
indeed, that's where I was a bit confused: I had 2000 or so trades min in the given example, we are not exactly talking about small numbers here?I'm sure it is just my pea brain not comprehending what you are saying, but if by "higher number of trades taken" you mean with reference to the total number of trades taken over a certain period of time (e.g., 5, 10, 20 plus) years then I completely agree with what you say. But if this is simply about saying: if your system has an edge then moving from say a max of 10 simultaneous open positions to a max of 20 simultaneous open positions then I don't agree with that. But I think you are referring to the former and not the latter?
I don't want to distract you from your current endeavors, but you might want to put this on your list of things to research in the future. To determine whether your 2000 trades is statistically relevant you need to put it into context. For example, if the 2000 trades was in the context of a possible 2 million trades then I would say 2000 trades is not a large enough sample size, but if the 2000 trades was in the context of a possible 3000 trades then I would say that is a good sample size. So how do you find out how many possible trades there are? You can easily do that in AB. I use the scan function (with a little AFL) to do a dump of all possible trades. You can use the output of the scan to see if your back test has taken a statistically relevant number of trades.indeed, that's where I was a bit confused: I had 2000 or so trades min in the given example, we are not exactly talking about small numbers here?
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