The document describes an implementation problem in pricing European calls with the inverse Gaussian component GARCH model of Babaoglu, Christoffersen, Heston, and Jacobs. The model has an exponentially affine moment generating function, allowing a…
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12,303 documents
The document asks how to interpret the local volatility shapes implied by a stochastic-local volatility specification related to SABR. In this setup, the forward rate is scaled by a power of its level, with the exponent controlling the backbone; the author…
The document asks whether a stock price can imply future volatility in the same way an option price does. The response explains that structural credit models can connect equity value to volatility because equity behaves like a claim on firm assets while debt…
The document explains how to turn observed zero-coupon yields into bond prices and estimate instantaneous forward rates from maturity changes. The proposed finite-difference calculation uses adjacent maturities to approximate the maturity derivative of the…
The document describes Markov-functional interest rate models as low-dimensional representations of the term structure built from functions of a Markov process. It notes their ability to calibrate to market prices and capture volatility smiles, while raising…
The discussion clarifies that a probability calculated from option implied volatility is not automatically a real-world forecast. Under Black–Scholes assumptions, the probability of finishing below a strike differs depending on the chosen pricing measure:…
This thesis-related question asks how to choose bounds for the Heston model parameters kappa, theta, sigma, and rho when generating synthetic data to train a neural network for calibration. It compares one published set of ranges, described as excluding…
This discussion considers a European call with an early-exercise feature that lets the holder exercise a portion and receive that portion’s current Black–Scholes value. The proposed replication is to hold the call and sell the corresponding fraction whenever…
The document describes a calibration problem for a Libor market model used to value a Bermudan swaption. The proposed volatility structure has a parametric time-to-maturity shape and period-specific scaling factors, while correlations follow an exponential…
The document asks how proprietary trading firms account for large intraday exposures when assessing annual trader performance with a PnL-to-VaR ratio. It distinguishes end-of-day ex-ante VaR, based on a trader’s positions, from risk estimates based on…
The document explains how to estimate a variance risk premium when the available inputs are probability densities rather than volatility estimates. It defines the premium, loosely, as the difference between objective and risk-neutral variance of future…
Implied volatility is the volatility input that makes an option pricing model, such as Black–Scholes, match an option’s market price. Because each strike, maturity, and option type is a distinct contract, each can trade at a different price and therefore…
The document asks whether two assets with equal return volatility can be combined into a product with greater percentage-return volatility, without simply using cash leverage. It considers a long-only linear combination and derives its variance from the…
The document clarifies a calculation for estimating volatility in a PRIIPs Category 2 stress scenario. The questioner first forms overlapping 63-day log returns, then calculates the standard deviation of those returns. The response says to calculate daily…
The discussion considers how to build an equity volatility surface when American and European options are listed on the same underlying and provide separate implied volatility observations at each maturity. One practical preference is to use European options…
The document explains how to infer implied correlation from an observed Margrabe option price. Given the two assets’ volatilities, prices, yields, and time to maturity, correlation determines the option’s relative volatility. The response notes that this…
The discussion examines why Black–Scholes can produce implausibly high values for very long-dated options. One explanation is that the model holds interest rates and volatility constant, even though both can change over time. The more detailed argument…
The discussion considers why an exchange rate might be modeled with geometric Brownian motion, a process whose proportional changes have a drift and a volatility term. With constant coefficients, its solution is an exponential of a drift-adjusted time…
The discussion examines the claim that a long calendar spread’s maximum loss is limited to its opening debit when the short option expires. In the usual intuition, if the underlying moves far below the strike, both calls lose value; far above it, both…
The discussion considers whether a constant displacement can adapt a standard LIBOR market model to negative interest rates. It proposes applying the shift to the forward rates used in the diffusion and drift numerators, while the accepted response clarifies…
The document works through the variance of a weighted basket when all asset returns have correlation one. For two assets, it writes the usual portfolio variance expression, including the covariance term, and recognizes that the expression becomes the square…
The document discusses how to calculate a one-year PRIIPs category 2 stress scenario for the Euro Stoxx 50 and why the reported value can change sharply between monthly KID dates. The response says the stress volatility should be based on rolling 21-day…
The document considers which volatility input to use when pricing options on futures with the Black model or a binomial tree. Its central point is that the appropriate volatility depends on the asset class and on which instrument provides the most relevant…
The document explains why variance swaps can serve as vega hedges and distinguishes several meanings of vega. A variance swap has sensitivity to its variance strike; option vega may instead refer to sensitivity to a parallel volatility shift or to changes in…