How Gamma and Vega Create Different Volatility Exposures

Summary

The explanation distinguishes gamma and vega as related but separate option exposures. Gamma is associated with sensitivity to realized volatility, while vega measures sensitivity to implied volatility. Traders who describe themselves as buying volatility, gamma, or vega generally mean they hold a position that can benefit from volatility, though the precise exposure depends on the Greeks in the portfolio.

Vanilla options carry both gamma and vega, but their relative amounts vary with maturity: near-expiry options tend to provide more gamma, while longer-dated options tend to provide more vega. This difference can be used to combine short- and long-dated options to target a portfolio that is long one exposure while approximately neutral to the other. The account is qualitative and gives no pricing formulas or hedge ratios; actual exposures depend on contract characteristics and the position’s rebalancing.

Key ideas

• Gamma and vega describe distinct option sensitivities and are not interchangeable terms.
• Gamma exposure is associated with realized volatility, while vega exposure is tied to implied volatility.
• Vanilla options typically carry both positive gamma and positive vega.
• Shorter-dated options tend to have more gamma, while longer-dated options tend to have more vega.
• Combining maturities can reduce one Greek while retaining exposure to the other.

Tags

# Vol, Gamma, Vega -- essentially all the same?


# Vol, Gamma, Vega -- essentially all the same?












When talking to traders I hear this sentence a lot

I am a buyer/seller of X

where X = {vol, gamma, vega}

Is X basically all the same -- they are just saying -- I think implied volatility is cheap or expensive?

Or is it something fancier, where they basically isolated the Greeks and are trading them one by one; in addition to trading implied vol?

## Answer by Chris Taylor (score 8, accepted)

https://quant.stackexchange.com/a/66700

They are not the same, but they are related.

Gamma is sensitivity to realized volatility. Vega is sensitivity to implied volatility. Vanilla options are always long gamma and long vega, so they are "long vol" and saying "I am a buyer of vol/gamma/vega" means that you are taking a position that benefits from a rise in volatility (either realized or implied).

Although vanilla options are long both gamma and vega, they are generally long in different amounts. Near expiry options have more gamma, and far expiry options have more vega. That means you can construct a long gamma/vega flat portfolio by buying short-term options and hedging the vega with a short position in long-term options, or you can construct a gamma flat/long vega portfolio buy buying long-term options and hedging the gamma with short-term options. Each of these portfolios would be "long vol" but one is only long gamma, and the other is only long vega.

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This summary was written by Stratmill's research agent from the original; it is not a copy of the source.