Hi - Can't give you a definitive answer, but the scan will return the 
  
*signals*, all of which might not have been taken by the backtester for a 
  
variety of reasons. You might check your AA settings, the backtester may 
  be 
removing redundant signals, you may have run out of available cash, 
  etc, 
etc....
Steve
----- Original Message ----- 
From: 
  "professor77747" <professor@xxxxxxxxx1.biz>
To: 
  <amibroker@xxxxxxxxxps.com>
Sent: 
  Saturday, August 30, 2008 2:43 PM
Subject: [amibroker] Why is scan and 
  backtest different?
>I have a formula that I backtest and trade. I 
  noticed that for a
> period of 2 weeks and a few other times. The 
  backtest didn't show a
> trade when the scan showed buy and 
  sell.
>
> The backtest had this for the period from April 1,2008 
  to April
> 18,2008.
> Statistics | Charts | Trades | Formula | 
  Settings | Symbols
>
> Trades
>
> Trade list Ticker 
  Trade Entry Exit % change Profit Shares Pos. value
> Cum. profit # bars 
  Profit/bar MAE/MFE Scale In/Out
> ZG DEC 08-ECBOT-FUT Open Short 
  04/18/2008 4:30:00 PM
> 935.3 04/18/2008 4:30:00 PM
> 935.3 0.00% 
  -4.80
> -4.80% 1 100.00 -4.80 2 -2.40 -2.32%
> 1.24% 
  0/0
>
> Notice that it had only a trade on the last 
  day.
>
> This is the scan results for the same period.
> 
  Ticker Trade Date Close
> ZG DEC 08-ECBOT-FUT Buy 04/02/2008 
  919.1000
> ZG DEC 08-ECBOT-FUT Cover 04/02/2008 919.1000
> ZG DEC 
  08-ECBOT-FUT Buy 04/03/2008 4:30:00 AM 919.1000
> ZG DEC 08-ECBOT-FUT 
  Cover 04/03/2008 4:30:00 AM 919.1000
> ZG DEC 08-ECBOT-FUT Buy 
  04/03/2008 4:30:00 PM 920.2000
> ZG DEC 08-ECBOT-FUT Cover 04/03/2008 
  4:30:00 PM 920.2000
> ZG DEC 08-ECBOT-FUT Buy 04/04/2008 4:30:00 AM 
  918.0000
> ZG DEC 08-ECBOT-FUT Cover 04/04/2008 4:30:00 AM 
  918.0000
> ZG DEC 08-ECBOT-FUT Buy 04/04/2008 4:30:00 PM 
  924.4000
> ZG DEC 08-ECBOT-FUT Cover 04/04/2008 4:30:00 PM 
  924.4000
> ZG DEC 08-ECBOT-FUT Sell 04/09/2008 4:30:00 AM 
  920.0000
> ZG DEC 08-ECBOT-FUT Short 04/09/2008 4:30:00 AM 
  920.0000
> ZG DEC 08-ECBOT-FUT Buy 04/11/2008 4:30:00 PM 
  938.2000
> ZG DEC 08-ECBOT-FUT Cover 04/11/2008 4:30:00 PM 
  938.2000
> ZG DEC 08-ECBOT-FUT Sell 04/13/2008 930.7000
> ZG DEC 
  08-ECBOT-FUT Short 04/13/2008 930.7000
> ZG DEC 08-ECBOT-FUT Sell 
  04/18/2008 4:30:00 PM 935.3000
> ZG DEC 08-ECBOT-FUT Short 04/18/2008 
  4:30:00 PM 935.3000
>
> Why don't these buy and sell have trades 
  made in the backtest.
>
> I have about 41 trades in a 5 months 
  backtest and about 5 are
> missing. So out of a possible 46 trades the 
  backtest only shows 41.
>
> On my chart, I have arrow that show 
  trading signals. The arrows are
> on the chart, but the backtest doesn't 
  show the trades.
>
> What would cause this to 
  happen?
>
> Tom
>
>
> 
  ------------------------------------
>
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