Define the Term ‘Implied Probability’ as It Relates to an Option’s Delta.

The Delta of an option can be used as a close approximation for the market's implied probability that the option will expire In-the-Money (ITM). For a European call option, the Delta is mathematically related to the cumulative normal distribution function, which represents the probability of the asset price being above the strike price at expiration.

Therefore, a Delta of 0.65 for a call option suggests the market believes there is approximately a 65% chance the call will expire ITM. This is a heuristic, not a precise probability.

Can an ITM Option Still Expire Worthless?
Define ‘In-the-Money’ (ITM) for Both Call and Put Options
Can a Synthetic Long Position in the Underlying Asset Be Created Using American Options?
Can an OTM Option Expire ITM?
Define the Term “Tail Risk” and How It Relates to Short-Term Hedging
Why Is It Risky to Hold an Out-of-the-Money Option into Expiration?
How Does the Delta of an Option Relate to Its ITM, ATM, or OTM Status?
What Is Delta in the Context of Options Trading?

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