Robustness is a tough discussion to have as it can go many different 
places ...

In one of its simplest forms ( which is how I like to keep it ) 
robustness is to at least some degree a function of the robustness of 
the parameter values ( those you choose to optimize AND most of those 
you believe for some reasons are constants ).  Looking at this from 
the view of the parameters ... the less sensitive the parameters are 
the more robust your system is likely to be ...

With a two parameter system how sensitive the parameters are can be 
seen by looking at the 3d charts that are part of AmiBroker i.e. what 
happens to the performance metric you have on the Z-axis as the 
parameter values change ... With more than two parameters the process 
is a little more difficult.  One way to test the sensitivty of the 
existing parameter values is to simultaneously test randomly 
generated values for each of the parameters in the +/- n% range from 
the values that you or optimization has picked.  The output will be a 
collecion of optimization lines or backtests if you will that will 
demonstrate how sensitive your parameters are.  This is an automated 
feature of the shareware version of IO i.e. to perform the random 
tests and plot the results in histogram format.

--- In [email protected], "dingo" <[EMAIL PROTECTED]> wrote:
>
> As far as "this is a whole another issue" - I seriously doubt 
that's the
> case.  Sounds like the same general problem to me.
> 
> Download IO.zip and read thru the docs and see if any of that makes 
sense to
> you...
> 
> d  
> 
> > -----Original Message-----
> > From: [email protected] 
> > [mailto:[EMAIL PROTECTED] On Behalf Of intermilan04
> > Sent: Wednesday, August 30, 2006 7:32 PM
> > To: [email protected]
> > Subject: [amibroker] Re: Backtest vs Forwardtest
> > 
> > I wish I was making 75% up to now :-)
> > The 75% is the result of my system which is optimized between 
> > 2001-2006.  Since I'm always trying to improve my system, I 
> > don't necessarily have traded with the system verbatim from 
2006/1/1.
> > 
> > Now I am having an issue where as soon as I start using a 
> > system its performance drops :-D  but this is a whole another 
> > issue so I didn't mention about it here.
> > 
> > intermilan04
> > 
> > --- In [email protected], "sebastiandanconia"
> > <sebastiandanconia@> wrote:
> > >
> > > Nope, I just meant that he measured all the other years from 
> > > Jan.1-Jan.1, so he's not comparing apples to apples by 
> > looking at YTD 
> > > performance.  We're coming into a time of year when there are 
> > > typically major drops followed by major rallies, so if his 
system 
> > > captures that behavior it could make up for its miserable 
> > 75% profit 
> > > up until now.:)
> > > 
> > > I hear you about real DD's that exceed that of tested 
> > methods.  That's 
> > > why I think it's so important to understand why a system 
> > works, beyond 
> > > simply the fact that it's tested-out well, which could just be 
a 
> > > mathematical coincidence, a meaningless correlation without any 
> > > cause-and-effect relationship.
> > > 
> > > 
> > > Luck,
> > > 
> > > Sebastian
> > > 
> > > --- In [email protected], "Fred" <ftonetti@> wrote:
> > > >
> > > > "So, two things: First, the obvious one, you can't really 
> > know that 
> > > > your system has "broken down" until you get the final results 
on 
> > > > January 1, 2007.:)"
> > > > 
> > > > Really ? ... You mean there is no point at which real DD's 
exceed 
> > > > previous experience you wouldn't think that system is broken ?
> > > >
> > >
> > 
> > 
> > 
> > 
> > 
> > 
> > Please note that this group is for discussion between users only.
> > 
> > To get support from AmiBroker please send an e-mail directly 
> > to SUPPORT {at} amibroker.com
> > 
> > For other support material please check also:
> > http://www.amibroker.com/support.html
> > 
> >  
> > Yahoo! Groups Links
> > 
> > 
> > 
> >  
> > 
> > 
> > 
> > --
> > No virus found in this incoming message.
> > Checked by AVG Free Edition.
> > Version: 7.1.405 / Virus Database: 268.11.7/433 - Release 
> > Date: 8/30/2006
> >  
> >
>







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