Forums > Which strategies work, and which don't

May 3rd, 2012, 09:31 PM   #31
SteveNYC

Join Date: Jul 2010
Posts: 895
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 Quote from failed_trad3r: wait, do you daytrade?

yeah, do you day trade?
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May 3rd, 2012, 09:32 PM   #32
SteveNYC

Join Date: Jul 2010
Posts: 895
Quote:
 Quote from jcl: Highpass, lowpass, and bandpass filters. This is the lite-C code for a simple second degree lowpass filter: Code: ```var smoothF(int period) { return 2./(period+1); } var LowPass(var *Data, int Period) { var *LP = series(*Data,3); var a = smoothF(Period); var a2 = a*a; return LP[0] = (a-a2/4)*Data[0] + 0.5*a2*Data[1] - (a-0.75*a2)*Data[2] + 2*(1.-a)*LP[1] - (1.-a)*(1.-a)*LP[2]; }``` This is no moving average. MA crossing strategies are normally not profitable because of lag. Using such filters in trade strategies is described on a website to which I can't post a link here out of consideration for the sponsors of this forum. I already got chastised by a moderator for posting too much info.

Do you have a screen shot of this filter?
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 May 4th, 2012, 01:47 AM #33 jcl     Join Date: Jan 2012 Location: http://dictionary.of-the-infinite.com Posts: 407 SteveNYC: A chart of a lowpass filter was posted here some months ago, look for a thread titled like "extremely simple profitable strategies" or similar. And no, I do not day trade. My computer does. Quote
May 4th, 2012, 07:35 AM   #34
ssrrkk

Join Date: Jun 2005
Posts: 440
Quote:
 Quote from jcl: This is no moving average. MA crossing strategies are normally not profitable because of lag.
You mean second or higher order filters work, I guess. First order low pass = exponential moving average. So you are saying that going from first order to second order filters makes an unprofitable system become profitable. I suppose it's plausible, but I still haven't had the chance to check.
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May 4th, 2012, 08:27 AM   #35
jcl

Join Date: Jan 2012
Location: http://dictionary.of-the-infinite.com
Posts: 407
Quote:
 Quote from ssrrkk: So you are saying that going from first order to second order filters makes an unprofitable system become profitable. I suppose it's plausible, but I still haven't had the chance to check.
If a system is profitable depends on many factors, not alone on the filter. But it's certainly easier to write a profitable system with a second order filter, than with an EMA. The filter catches market changes earlier because it has far less lag. You can easily test this when you have a trade platform with a C style language - just replace the EMA with my code above.
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May 7th, 2012, 06:39 PM   #36
Mysteron

Join Date: Apr 2010
Location: UK
Posts: 437
Quote:
 Quote from jcl: Highpass, lowpass, and bandpass filters. This is the lite-C code for a simple second degree lowpass filter: Code: ```var smoothF(int period) { return 2./(period+1); } var LowPass(var *Data, int Period) { var *LP = series(*Data,3); var a = smoothF(Period); var a2 = a*a; return LP[0] = (a-a2/4)*Data[0] + 0.5*a2*Data[1] - (a-0.75*a2)*Data[2] + 2*(1.-a)*LP[1] - (1.-a)*(1.-a)*LP[2]; }``` This is no moving average. MA crossing strategies are normally not profitable because of lag. Using such filters in trade strategies is described on a website to which I can't post a link here out of consideration for the sponsors of this forum. I already got chastised by a moderator for posting too much info.
This filter certainly has the characteristic frequency response of a low pass filter. Unfortunately the charting tools I use don't have the capability to evaluate it but I note it can be rewritten as:

EMA( EMA( (1/a-0.25)*Data[0]+0.24*Data[1]-(1/a-0.75)*Data[2] ))

where EMA is the standard EMA function.

Why not use the zero lag EMA which is first order and not as lagging as a standard EMA, although it isn't a low pass filter:

EMA( 2*Data[0]-Data[k] ) with k=1 or k=2
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