----- Original Message -----
Sent: Sunday, April 23, 2006 6:56
PM
Subject: [amibroker] Why portfolio
backtester does not consider all buy signals?
Hello:
Maybe somebody can explain this to me. I
believe I must have missed something, otherwise this would be a
critical fault in the backtester.
I backtested a simple dip buying system
against a portfolio of all common stocks (using QP3 quotes) for the month
of 1/2005. I turned on the detailed log so that I can examine how it
would trade. Then I ran an exploration to get a list of signals
on date 1/4/05. When I compared the signals from exploration and those
showed in the detailed log (for date 1/5/05, since there was one day
delay), I found that the detailed log didn't take all the signals with the
highest position scores.
I did similar comparison with other systems,
and had the same observation. I have not found any setting that can force
backtest to consider all signals.
System:
SetOption
("InitialEquity", 30000);
SetOption("CommissionMode", 1);
//$$ per trade
SetOption
("CommissionAmount", 0.3);
SetOption
("MarginRequirement", 100);
SetOption
("UsePrevBarEquityForPosSizing",
True);
SetTradeDelays
( 1, 1, 1, 1 );
RoundLotSize = 5;
Sell = (C>=Ref(C, -1))
AND (Ref(C,-1)>=Ref(C,
-2));
Buy = (C<Ref(C, -1))
AND (Ref(C, -1) < Ref(C,
-2));
SetPositionSize
(10, spsPercentOfEquity);
PositionScore = 100 - ROC(C, 4);
Filter = Buy OR
Sell;
AddColumn
( IIf( Buy, Asc("B"),Asc("S") ), "Signal",
formatChar );
AddColumn
(C, "Close");
AddColumn
(MA(V,50)*0.05, "MA50 Vol
5%");
AddColumn
(IIf(Buy, PositionScore, 0), "PositionScore", 1.5);
Detailed Log: (I run a backtest for the
month of January 2005).
1/4/2005,,,,,,,,,,,,,,,,,,,,,,
,Entry
signals(score):APT=Buy(112.919), TOPT=Buy(111.713), ITCD=Buy(111.429),
BED=Buy(111.404), SUPG=Buy(111.079), CNTY=Buy(111.029), RUBO=Buy(110.867),
IVN=Buy(109.934), JMAR=Buy(109.929), NAVI=Buy(109.926), KEYW=Buy(109.848),
PARS=Buy(109.804), M...,,,,,,,,,
,Exit
signals:,,,,,,,,,,,,,,,,,,,,,
,10 Open Positions: , AZL (+530), , LTRX
(+2675), , RTK (+1345), , TGC (+11535), , SCON (+215), , FISI (+125), ,
HDSN (+2650), , BITS (+1125), , AVSR (+2235), , ADAM (+740), Equity:
28768.5, Cash: 46.8594
1/5/2005,,,,,,,,,,,,,,,,,,,,,,
,Entry signals(score):ENG=Buy(122.257), MBAY=Buy(120.382),
TIV=Buy(120.055), MFRI=Buy(119.157), ANLT=Buy(118.644), KKD=Buy(118.125),
VLTR=Buy(118.099), NVTL=Buy(117.766), WPSC=Buy(117.058), IAO=Buy(116.667),
ACU=Buy(116.125), AKS=Buy(116.098),
TELO...,,,,,,,,,
,Exit signals:ADAM=Sell, ADSX=Sell,
APOL=Sell, ATLO=Sell, AVSR=Sell, BCRX=Sell, BFAM=Sell, BKSC=Sell,
CAC=Sell, CCOW=Sell, CDMS=Sell, CELL=Sell, CG=Sell, CGN=Sell, CHEV=Sell,
CITP=Sell, CNAF=Sell, CSWC=Sell, CTZN=Sell, DAIO=Sell, DEAR=Sell,
DEBS=Se...
,Exit Long, LTRX, Price: 1.15, (Avg. exit pr. 1.15), Shares:
2675, Commission: 9.22875, (Total comm.: 18.2168), Profit: 62.0332 (2.07
%), Entry rank:115.126, Equity: 28237.2, Fx rate: 1,,,,,,,,,,,
,Exit
Long, HDSN, Price: 1.11, (Avg. exit pr. 1.11), Shares: 2650, Commission:
8.8245, (Total comm.: 17.808), Profit: -70.808 (-2.36 %), Entry
rank:111.765, Equity: 28237.2, Fx rate: 1,,,,,,,,,,,
,Exit Long, AVSR,
Price: 1.45, (Avg. exit pr. 1.45), Shares: 2235, Commission: 9.72225,
(Total comm.: 18.707), Profit: 227.143 (7.58 %), Entry rank:111.333,
Equity: 28237.2, Fx rate: 1,,,,,,,,,,,
,Exit Long, ADAM, Price: 4.1,
(Avg. exit pr. 4.1), Shares: 740, Commission: 9.102, (Total comm.:
18.093), Profit: 18.9068 (0.63 %), Entry rank:110.962, Equity: 28237.2, Fx
rate: 1,,,,,,,,,,,
,Enter Long, ENG, Price: 2.41, Shares: 1190,
Commission: 8.6037, Rank: 122.257, Equity 28220, Margin Loan: 0, Fx rate:
1,,,,,,,,,,,,,
,Enter Long, MBAY, Price: 7.49999, Shares: 380,
Commission: 8.54998, Rank: 120.382, Equity 28202.9, Margin Loan: 0, Fx
rate: 1,,,,,,,,,,,,,
,Enter Long, TIV, Price: 8.25, Shares: 345,
Commission: 8.53875, Rank: 120.055, Equity 28185.8, Margin Loan: 0, Fx
rate: 1,,,,,,,,,,,,,
,Enter Long, MFRI, Price: 9.1, Shares: 315,
Commission: 8.5995, Rank: 119.157, Equity 28168.6, Margin Loan: 0, Fx
rate: 1,,,,,,,,,,,,,
,10 Open Positions: , AZL (+530), , RTK (+1345), ,
TGC (+11535), , SCON (+215), , FISI (+125), , BITS (+1125), , ENG (+1190),
, MBAY (+380), , TIV (+345), , MFRI (+315), Equity: 28289.1, Cash:
837.545
Exploration Results sorted by position
score: (the ones in pink were taken by
backtester)
Ticker,Date/Time,Signal,Close,MA50 Vol
5%,PositionScore,
AZL,1/4/2005,B,4.20,2117.90,132.69231
CLWT,1/4/2005,B,4.12,20596.03,126.29697
OLAB,1/4/2005,B,3.10,5782.43,124.18093
AGIX,1/4/2005,B,18.24,68695.09,123.71393
RTK,1/4/2005,B,1.86,20343.30,122.50000
ENG,1/4/2005,B,2.48,4869.30,122.25705
MBAY,1/4/2005,B,7.50,13010.61,120.38217
BDY,1/4/2005,B,15.75,20346.20,120.17233
TIV,1/4/2005,B,8.73,5775.60,120.05495
MFRI,1/4/2005,B,8.82,3541.42,119.15674
ABIX,1/4/2005,B,9.00,24999.93,118.91892
ANLT,1/4/2005,B,2.88,59164.97,118.64407
ADBL,1/4/2005,B,22.15,35483.04,118.56618
KKD,1/4/2005,B,10.48,123253.60,118.12501
CTG,1/4/2005,B,4.75,2408.90,118.10345
VLTR,1/4/2005,B,17.92,15662.28,118.09872
NVTL,1/4/2005,B,16.20,84408.39,117.76649
SMSI,1/4/2005,B,8.08,33207.16,117.71894
KEYW,1/4/2005,B,16.96,17987.54,117.54984
VLLY,1/4/2005,B,35.80,1717.97,117.32101
AFOP,1/4/2005,B,1.26,5090.44,117.10526
WPSC,1/4/2005,B,33.21,5254.02,117.05795
DHB,1/4/2005,B,16.53,112250.30,116.80926
SUPG,1/4/2005,B,5.84,52530.34,116.69044
IAO,1/4/2005,B,0.35,7682.40,116.66666
............