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Calculate Black-Scholes implied volatility

Source: R/blackscholes_impvol.R
BlackScholesImpvol.Rd

Calculate Black-Scholes implied volatility

Usage

BlackScholesImpvol(
  price,
  strike = forward,
  spot,
  texp = 1,
  intr = 0,
  divr = 0,
  cp = 1L,
  forward = spot * exp(-divr * texp)/df,
  df = exp(-intr * texp)
)

Arguments

price

(vector of) option price

strike

(vector of) strike price

spot

(vector of) spot price

texp

(vector of) time to expiry

intr

interest rate (domestic interest rate)

divr

dividend/convenience yield (foreign interest rate)

cp

call/put sign. 1 for call, -1 for put.

forward

forward price. If given, forward overrides spot

df

discount factor. If given, df overrides intr

Value

Black-Scholes implied volatility

References

Giner, G., & Smyth, G. K. (2016). statmod: Probability Calculations for the Inverse Gaussian Distribution. The R Journal, 8(1), 339-351. doi:10.32614/RJ-2016-024

See also

BlackScholesPrice

Examples

spot <- 100
strike <- 100
texp <- 1.2
sigma <- 0.2
intr <- 0.05
price <- 20
FER::BlackScholesImpvol(price, strike, spot, texp, intr=intr)
#> [1] 0.4023459