Quote from lasner:
I'm trying to figure how options will move in different scenarios. Is there any way to get an idea of what will happen.
The easy way is to download a free P/L tool such as <a href="http://www.samoasky.com/">
www.samoasky.com/</a> and play with it a bit.
To really understand it better here is some info I posted in another thread:
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To really understand what will happen to an option you really need to understand all of the Greeks (of which Delta and Theta are the two most important):
Delta: This is the amount the options price will move as the underlying price moves UP. The value will always be a number between 1 and -1. A positive value means the option will move up as the underlying moves up and a negative number means the option will go down as the underlying moves up.
Theta: Is the measure of time decay. This is the amount the option will lose per day as the option gets closer to expiration. Things that affect Theta include: Time to expiration and how far in or out of the money the option is.
Gamma: Is basically the rate of acceleration in Delta. In other words it measures how much the Delta of an option will increase or decrease based on a $1 move in the underlying.
Vega: Is the amount the options price will change in theory as the implied volatility changes. The change from Vega only usually applies to the time value of the option which in combination with Theta controls the time value of the option.
Ro: This little guy isn't too important but I will mention it for the sake of completeness. Ro is a measure of how much the options value will change based on a 1% change in interest rates.
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How can this all be used? In the other thread someone provided the following example:
for example lets say the price of option abc is $1.00 and it has a $10 strike and a delta of $0.10. the underlying stock rises $5 making the price of abc $1.50. would the price really be $1.50 or does the delta rise as the stock gets closer to its stock price? is the delta calculated by the options past performance? if so is delta a reliable indicator for what the option will be or is it more like a guide?
My response was:
It would depend largely on how long the underlying took to reach that $5 move. If it did it in 1 day and the option had a Delta of .1 and a Theta of -.05 then the value of the option the next day would only be $1.25.
If the stock took 3 days to move that $5 with a Delta of .1 and a Theta of -.05 then the options value would only be about $0.75.
Adding in the effects of Gamma to the 3 day example, the option value might end up anywhere between $0.90 (assuming Gamma of .02) and $1.65 (assuming Gamma of .06).
This does not even take into account Vega or what the volatility is doing.