How do I determine odds in a credit spread?

Discussion in 'Risk Management' started by dcwriter2, Jun 20, 2021.

  1. I'm tinkering with the Kelly formula and it makes sense except when it asks me for the odds. Does that mean if I am writing a spread with delta of -.98, way out there, my odds are 1:98 and how is that expressed in a percentage or decimal?
     
  2. destriero

    destriero

    A put credit spread is a call debit spread.

    It doesn't work that way. Price the opposing side (2D put) as a digital. You're fucked beyond reason on a touch so what does it matter what the odds are?
     
    maiimli likes this.
  3. Ok, I'm writing bear call spread, at least that's what IB calls it. Way OTM, like one wing of an iron condor, ok? Now what are the odds that I would plug in for the Kelly?
     
  4. destriero

    destriero

    Kelly works well in digitals (AON payoff) but not when laying stupit odds. This may not be the best career choice for you at this time.
     
  5. BKR88

    BKR88

    Not an options greek trader but my dummy math says -.98 = 98% chance of ending OTM so 2% (.02) chance ending ITM.
     
  6. So how does that translate into "odds"?
     
  7. destriero

    destriero

    2% probability of losing it all at exp. 4% prob of losing it all tomorrow. Go back to 9th grade.

    Baron, permission my block, plz. I'll be good.
     
  8. Overnight

    Overnight

    Well that would suck, I'll be the first one on the list! BAH!

    I better get in my music bits now!

     
  9. BKR88

    BKR88

    2% chance = 2:100 odds = 1:50 odds price ends ITM
    98:100 odds = 49:50 odds price ends OTM
     
    Last edited: Jun 21, 2021
    dcwriter2 likes this.
  10. MrMuppet

    MrMuppet

    That's a good way to blow up your account^^

    The "odds" you're talking about are implied by the options prices...and they don't necessarily mirror your true odds. The true return distribution is unknown and you're betting against it by buying cheap implied distribution and selling expensive distribution via options.

    If you're selling cheap "odds" against expensive realized distribution you trade at negative edge. Add full Kelly to it and your risk of ruin is 100%
     
    #10     Jun 21, 2021
    Lou Friedman likes this.