[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [amibroker] Total Performance question?



PureBytes Links

Trading Reference Links




<SPAN 
class=338271521-02112003>I don't get your context. total change in what? price 
of the current stock? start and end prices I think would be:
<SPAN 
class=338271521-02112003>
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>price_at_start_of_test = 
LastValue(ValueWhen(Status("FirstBarInRange"), c));price_at_end_of_test = 
LastValue(ValueWhen(Status("LastBarInRange"), c));
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>do that, then add these columns and explore to 
verify:
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>AddColumn(start_price, 
"price_at_start_of_test");AddColumn(end_price, 
"price_at_end_of_test");AddColumn(c, "c");
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>percentage change would be:
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>pct_change = ((end_price / start_price) - 1) * 
100;
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>some major caveats though...
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>- if you're talking about price change over the course 
of the same backtest that's running now, the backtester itself tells you that, 
so I don't understand what you're trying to do.
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>- if you make buy/sell decisions based on the above, 
you're looking into the future, and you won't be able to trade like that in real 
life. that's why you have to use LastValue, so you can see what the value 
would be as of the last bar.
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>- code that runs during a backtest runs *before* 
the portfolio calculations have been done. in a scoring or rotational system, 
you can't even tell which of the buys and shorts you set up will actually get 
taken, and which will be outscored by another stock and 
skipped.
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>all of that's what I thought when I saw your first msg. 
I figured I didn't have anything useful to say about it then, since I must have 
misunderstood the point. which I do frequently, it seems...
<SPAN 
class=338271521-02112003> 
<SPAN 
class=338271521-02112003>dave
<BLOCKQUOTE 
>I'm 
  trying to figure out how to determine the Total Percent Changein the Close 
  from the... From Date thru the To Date in my backtest.I'm looking for 
  the value of the Close on the FromDate and also onthe ToDate, so i can 
  compute Total Percentage Change between the 2 dates.I obviously 
  don't understand barinrange yet, and if someone can helpme figure this out 
  i'd truly appreciate it. Thank 
you.Bill






Yahoo! Groups Sponsor












Send BUG REPORTS to bugs@xxxxxxxxxxxxx
Send SUGGESTIONS to suggest@xxxxxxxxxxxxx
-----------------------------------------
Post AmiQuote-related messages ONLY to: amiquote@xxxxxxxxxxxxxxx 
(Web page: http://groups.yahoo.com/group/amiquote/messages/)
--------------------------------------------
Check group FAQ at: http://groups.yahoo.com/group/amibroker/files/groupfaq.html



Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.