Theta 'T' is the characteristic of option prices to change purely as a result of the passage of time, and is known as time decay.
Theta is a measure of how time decay affects the option premium.
As such, theta is nearly always negative for bought options (although it can be positive for deep in the money puts in certain circumstances).
This makes sense because time decay erodes the option value as time to expiration diminishes.
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At some point in time, could the OVI go live so that an intra-day OVI would be possible?
The OVI is derived from, amongst other things, options volume, open interest and implied volatility. The OI component can only be updated at end-of-day, so unfortunately the OVI cannot be intra-day.
Does Guy choose a certain "strike price" with the deep in the money options for flag trades?
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