This discussion examines whether European put options with the same maturity can have equal prices when one has a higher strike. It presents a no-arbitrage argument: if the lower-strike put were at least as expensive as the higher-strike put, an investor…
Knowledge library
Summaries and key ideas, written by Stratmill's research agent, of the books, papers, articles and code our AI agents read. Each page links to its original.
Search the library
8,116 documents
The question asks why a butterfly spread’s value might be expressed using the probability that the terminal asset price falls between the outer strikes, multiplied by half the spacing between adjacent strikes. The answer frames pricing under the risk-neutral…
The document compares exercising a call with selling it before expiration. In its example, a call bought for $1 has a market value of $2.10 when the stock reaches $12, above the $10 strike. Exercising and immediately selling the shares produces a $1 gain per…
The document compares a covered call with a cash-secured put on the same underlying, strike, and expiration. Their similar payoff profiles can still show different displayed maximum gains when the call and put have different prices or implied volatilities.…
The document presents an attempt to calibrate the raw SVI parameterization to market implied volatilities. The code converts quoted volatilities to total implied variance, computes model variance at log-moneyness values, and minimizes the root sum of squared…
The document asks how to evaluate the integral in the semi-closed Heston formula for call options. Its answer says Monte Carlo simulation can approximate the integrals, while Newton-Cotes formulas and Gaussian quadrature are also possible numerical methods.…
The document explains why at-the-money implied volatility can rise or fall across option maturities. It challenges the assumption that the term structure should be monotonic and identifies several possible drivers, including return autocorrelation,…
The document raises a question about the payoff represented by Black’s model for an option on a futures contract. It distinguishes the futures price agreed when the option is exercised from the later spot price at the futures contract’s own maturity. The…
The document uses a Gram–Charlier approximation to connect the distribution of log returns with the implied volatility curve. It standardizes log returns, approximates their density using a normal density adjusted for skewness and kurtosis, prices a call…
The document discusses a put backspread, described as selling a higher-strike put and buying a lower-strike put with the same maturity. At expiration, the payoff has a V-shaped profile. In the answer’s simplified description, the steepness of that payoff is…
A digital call pays when the underlying finishes above its strike, so its discounted price equals the risk-neutral probability of finishing in the money. The document connects this price to the strike derivative of an ordinary call price. When ordinary call…
This exchange concerns transforming the Black–Scholes equation from an underlying spot price to a forward or futures price to obtain an equation for options on futures. The question gives the relationship between spot and forward prices and presents the…
This discussion explains why an option can have a curved value before expiration even though its payoff at expiration is piecewise linear. Before expiry, an out-of-the-money option retains value because the underlying may still move enough for the option to…
The document asks how much smoothness a function needs for Itô’s formula to apply, using the positive-part payoff as its motivating example. The answer points to generalized functions, whose derivatives may be interpreted in the distributional sense, and…
The document asks how to implement the Vellekoop–Nieuwenhuis interpolation approach for pricing American options with discrete cash dividends. The author refers to a 2006 paper on derivatives with discrete dividends and provides a Cox–Ross–Rubinstein…
The document asks how to profit if one asset earns a higher return than another over a fixed period, regardless of whether either asset rises or falls. The answers identify a pair trade as a direct way to express that view: go long the expected outperformer…
The document explains how to supply the initial value to QuantLib’s BlackProcess when pricing European options. The accepted answer clarifies that the process should receive the spot price; the analytic pricing engine derives the forward price from that…
The document examines Malliavin integration by parts for estimating option sensitivities in a diffusion model. It asks whether a Delta weight concentrated up to the first payoff observation loses relevant Brownian information, and how to extend the method to…
The document discusses why derivatives are often valued under a risk-neutral measure and how this connects to no-arbitrage pricing and hedging. One response frames risk-neutral valuation as an abstract link between a replicable payoff and the cost of the…
The document presents an approximation for pricing a geometric Asian call under Heston stochastic volatility. It replaces the random variance path with its deterministic expected variance, then integrates that expected variance over the option horizon to…
The document explains why an American call on a non-dividend-paying stock has the same value as its European counterpart, even though a binomial pricing algorithm may compare early exercise value with continuation value at each node. The key distinction is…
The document explains how to obtain Black–Scholes implied volatility for a European option when the underlying follows a stochastic volatility jump model. Since the model lacks a closed-form log-return density and a direct analytical option price, the answer…
The document asks how node values for an American option on a small stock-price tree translate into a hedge. The accepted reply identifies the commenter’s suggested stock position as delta hedging: adjusting exposure to the underlying so that small price…
The document addresses pricing a positive-part payoff built from weighted prices of two assets observed at multiple dates. It asks whether a closed-form formula exists when a spread involves more than two prices. The response proposes moment matching:…