Mike,

Thank you for this information, it was very helpful. I can understand pain 
versus gain better. That is what I wanted to know. How can I use the statistics 
to know which have more gain versus pain.

Tom

--- In [email protected], "Mike" <sfclimb...@...> wrote:
>
> Tom,
> 
> There are any number of formulas people use to evaluate results. Many follow 
> the axiom of "no pain, no gain" and are expressed in the form of a ratio or 
> as numerator over denominator. These simply describe how much pain had to be 
> endured in order to accumulate the gain.
> 
> With that in mind, you should be able to figure out which part of the 
> equation represents the pain, which part represents the gain, and whether a 
> large number is good or bad. Hint; Variance, as expressed by standard 
> deviation, is pain.
> 
> Using one of your examples; A big CAR (gain) is only part of the equation. 
> When you also taken into consideration the MDD (pain) you may not be as 
> attracted to the strategy. A 50% CAR would be great, but not as palatable 
> when the cost is a 75% drawdown. Too much pain for the gain. Most would 
> prefer less pain (lower MDD) even if it meant a lower gain.
> 
> Note that CAR/MDD can result in a larger number in either of two ways: A 
> large CAR over a moderate MDD, or a moderate CAR over a small MDD. As such, 
> trying for a smaller MDD is as benificial as trying for a large CAR, and 
> trying for both gives even better results.
> 
> Answering your specific questions:
> 
> - 12 is bigger than 2, so yes a CAR/MDD of 12 is good. You have experienced 
> 12 times more gain than pain.
> 
> - The K-Ratio description is out of date. The formula has since been revised 
> such that (according to Howard Bandy) 0.15 or better is good. Note that 
> K-Ratio uses standard deviation and so penalizes positive variance as much as 
> negative variance. Some people prefer to use ulcer index for this reason. See 
> http://www.tangotools.com/ui/ui.htm
> 
> - A lower ulcer index is better. As suggested by the name, a bigger ulcer 
> means more pain.
> 
> - I have found Bandy's approach to finding a fitness function usefull. He 
> suggests that a good way to decide whether a measure suits your personal 
> preferences is to look at the equity curve of a number of different 
> strategies or parameter combinations and arrange them in order of best to 
> worst (based solely on what you feel about the chart). Then look at the 
> measurements and see whether the progression of values reflect your 
> arrangement.
> 
> For example; If the highest CAR/MDD was for your favorite chart, the next 
> highest CAR/MDD is for your next favorite, and so on all the way down to your 
> least favorite, then CAR/MDD would be a very good metric ("fitness function") 
> for you to compare strategies with, since it so closely correlates to the 
> type of equity curve that you favor.
> 
> Generally, measurements that contain both a gain element and a pain element 
> are good candidates for fitness. Looking at only one side (e.g. only CAR) or 
> the other (e.g. only MDD) generally does not work well in out of sample data.
> 
> Some candidates are CAR/MDD, RAR/MDD, Ulcer Index, UPI, K-Ratio, etc.
> 
> Mike
> 
> --- In [email protected], "professor77747" <professor@> wrote:
> >
> > Thank you for your replies. However, I have the way they are calculated, 
> > but I don't know what they mean. For instance, CAR/MaxDD is good if bigger 
> > than 2. My formula is over 12. Is that good?
> > 
> > However, the K-Ratio should be over 1.0. My forumula is .06. So that must 
> > be bad. 
> > 
> > I don't know how to judge my formula because I really don't understand how 
> > to interpret the figures.
> > 
> > What should the Ulcer Index be. Is higher better or worse.
> > 
> > I have just compared my formulas using Profit and Downdraw. I take the 
> > highest profit as long as the downdraw is close. 
> > 
> > Tom
> > 
> > --- In [email protected], "Mike" <sfclimbers@> wrote:
> > >
> > > http://www.amibroker.com/guide/h_report.html
> > > http://www.investopedia.com/categories/formulas.asp
> > > 
> > > Mike
> > > 
> > > --- In [email protected], "professor77747" <professor@> wrote:
> > > >
> > > > 
> > > > I have a very profitable formual that I have been autotrading for over a
> > > > year. However, it is also risky. I have another formula that is not as
> > > > profitable, but is also not as risky. My formula trade almost exactly as
> > > > a backtest except for the price which varies by so little that it is not
> > > > a factor.
> > > > 
> > > > I don't understand any of the risk % factors in the top section and the
> > > > factors below the drawdown figures in the bottom section.
> > > > 
> > > > Here is a link to the statistics for last year which are very similar to
> > > > this year except that there is more data. Statistics
> > > > <http://success101.biz/Backtest%20Report.htm>
> > > > 
> > > > Please help me understand these statistics. Thanks
> > > > 
> > > > Tom
> > > >
> > >
> >
>


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