Need input on max position size

Discussion in 'Risk Management' started by bln, Jan 21, 2022.

  1. bln

    bln

    What is the highest risk I can take with a strategy with the following metrics:

    Win/loss ratio: 79%
    Profit/loss ratio: 0.66
    Longest losing streak: 2
    Worst losing DD sequence: L-L-W-L-L

    How hard can one run this without blowing up.
     
    murray t turtle likes this.
  2. DevBru

    DevBru

    What is the draw down percentage? What time period do these statistics cover? How many trades is it based on?
     
    murray t turtle likes this.
  3. bln

    bln

    Duration: 6 years
    Trades: 95

    Max Draw Down in percent is a unknown parameter as it is a derived variable of the selected position risk in percent for each trade.

    Example of $10,000 equity and selected risk per trade is 5%, the MDD comes out like this:

    0.05 * 0.66 = 0.0330
    Risk per losing trade 5%, win per winning trade 3.3%

    (10000 * 0.95^4) * 1.033
    8413.84956250000 (equity after the max draw down)

    ((8413.85/10000)-1)*100 = -15.8615
    We get an MDD of -15.86%
     
    murray t turtle likes this.
  4. I recommend not using any leverage. 95 trades is a very small sample set. Despite having a nice looking backtest I guarantee you will have future periods where your performance is worse than this and you will question your strategy. If you use leverage you may have nothing left after a long period of losing trades.
     
    murray t turtle likes this.
  5. %%
    6 years maybe enough?? NOT likely 2 will be the longest lose streak, its real strange how it seldom gets better , usually a bit worse.............................................................
     
  6. bln

    bln

    yes. long enough there will a longer losing streak than the current observed one.

    did some compound probability calcs.

    2 losing streak = 4.41% probability (5 streaks in 100 trades)
    3 losing streak = 0.92% (1 in 100)
    4 losing streak: 0.19% (2 in 1000)
     
    murray t turtle likes this.
  7. %%
    Great thing about beating the benchmark SPY; most dont do that 10 years in a row:D:D. So make sure to do SSO some /LOL
     
  8. easymon1

    easymon1

    murray t turtle likes this.
  9. bln

    bln

    One I have developed and have. Been trading it with real money since June and it's been performing good.

    Each trade is fixed loss and fixed win in dollar or percentage.
     
  10. easymon1

    easymon1

    Per your question, "What is the highest risk I can take with a strategy with the following metrics:"
    Ryan Jones' book on fixed ratio "The Trading Game" referenced above, and others, show methods of position sizing and managing money based on past performance. He compares the results of a few methods on account equity curve.
    To get Jones' view on the subject, just copy-paste the URL found in the link above into your browser address bar and see the math. Why fixed loss and fixed win?
     
    Last edited: Jan 27, 2022
    #10     Jan 27, 2022