Hi Curt -- When you make these runs, you will get the Monte Carlo results of selecting random portfolios. And you will see a wide variation in performance. If your system looks good to you, and you begin to trade it, how will you select which stocks to take positions in when there are more opportunities than funds? If you have some thoughts about that, incorporate those into your positionscore. The alternative is to shake the dice.
Thanks, Howard On Thu, Jan 22, 2009 at 12:27 PM, Keith McCombs <[email protected]>wrote: > TJ -- > "PositionScore SHOULD be an array." -- Thank you. > > "Microsoft's random" -- Who mentioned Microsoft's random? > I suggested exporting to a spread sheet for further analysis. For example, > I like to plot a histogram of the returns and scatter diagrams of different > metrics. > > -- Keith > > > Tomasz Janeczko wrote: > > That is incorrect. PositionScore SHOULD be an array. Also use mtRandomA() > instead. Mersene Twister is way way way better than Microsoft's random. > > Best regards, > Tomasz Janeczko > amibroker.com > > ----- Original Message ----- > *From:* Keith McCombs <[email protected]> > *To:* [email protected] > *Sent:* Thursday, January 22, 2009 7:13 PM > *Subject:* Re: [amibroker] Re: Using Optimizer with PositionScore=Random() > > Richard -- > runs = 1000; // Number of runs using random scores > TotalRuns = Optimize("TotalRuns", 1, 1, runs, 1); > PositionScore = LastValue(Random()); // need value, not array > -- Keith > > richpach2 wrote: > > Keith, > > How would you use Random() to set up an optimization to run say 1000 > iterations overnight? > > Regards > Richard > > --- In [email protected], Keith McCombs <kmcco...@...> wrote: > > > > Curt -- > > IMO, it makes a whole lot of sense. > > > > Notice that if your strategy could select many stocks to trade, if you > > do not use Random(), the system is biased to those stocks whose symbols > > are near the front of the alphabet. > > > > You can use Random() to set up an optimization to run say 1000 > > iterations overnight. Export the results to your favorite spread sheet > > and see a more realistic distribution of returns you might expect. > > -- Keith > > > > Curt wrote: > > > > > > --- In [email protected] <amibroker%40yahoogroups.com> > <mailto:amibroker% <amibroker%25>40yahoogroups.com>, > > > "Curt" <crcmcc@> wrote: > > > > > > > > Does it make sense to try to use the optimizer if PositionScore > is set > > > > to Random()? For example: > > > > > > > > OptimizerSetengine("cmae"); > > > > PositionScore = Random(); > > > > > > > I should clarify that by setting PositionScore=Random(), runs with > > > exactly the same parameters will not produce the same results. This is > > > because, in the cases where the portfolio becomes fully invested, a > > > different set of stocks will populate the portfolio each run. > > > > > > > > > > >
