The document explains how a Vasicek short-rate model changes under a risk-neutral measure and asks which parameters can be estimated from observed bond yields. It rewrites the adjusted drift using risk-neutral parameters, then relates yields to affine bond…
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10,263 documents
The document presents the risk-neutral Variance Gamma stock model, including its drift adjustment and the time-changed Brownian representation of the log return. It describes sigma as controlling volatility, while nu and theta jointly determine asymmetry and…
The document explains that collateralized debt obligations varied in complexity, but their payment structures can be analyzed by reading the governing deal documents. These contracts define cash-flow waterfalls tied to ratings triggers, collateral levels,…
The question asks whether the delta, gamma, vega, rho, and theta of a multi-asset product can be calculated by adding the corresponding Greeks of its underlying assets. The product described pays annual coupons when the performance of an equally weighted…
The document addresses how to estimate delta and gamma for a calendar spread option as the underlying spread changes, and asks whether empirical studies are available. The response models the calendar spread option as a position involving a short call at one…
The document explains how to think about intraday trading in currency forwards by relating a forward quote to the spot exchange rate and the cost of carry. It describes the forward as exposure to the underlying currency pair, adjusted for the interest-rate…
The document derives the fair one-year forward exchange rate by treating the two currencies as investable assets and applying the law of one price. It defines the spot quote as units of domestic currency L needed to buy one unit of currency Z, then compares…
The document explains why the VIX should not be expected to equal a quoted at-the-money implied volatility for SPX or SPY options. The key distinction is that VIX represents a variance-swap-style measure derived from a broad range of SPX option strikes,…
The document outlines ways to investigate persistent losses at a trading desk that sells structured bonds with embedded options and hedges them in the market. It first asks whether the products and hedges were intended to earn zero net P&L. If the desk…
The discussion asks whether a long-dated at-the-money straddle should use the strike nearest spot or the strike nearest the forward. The answer is that “at the money” depends on the market and product convention. Foreign exchange volatility quotes may define…
The discussion explains that the probability measure for a simulated asset path should match the simulation’s purpose. For derivative valuation, it recommends the risk-neutral measure, using the risk-free rate as the drift so simulated prices are consistent…
The document works through Itô’s formula for a function of two time-varying state variables, each with drift and diffusion terms driven by correlated Brownian motions. It explains that the second-order expansion includes a mixed derivative, and that the…
The document asks why a deep out-of-the-money SPX call at a round-number strike can show substantial trading volume, and whether it belongs in data used to construct an option-implied risk-neutral distribution. The responses suggest checking open interest…
The document asks for papers or books on pricing debt instruments that allow prepayment. The author has found general material on callable bonds but wants references explaining whether a prepayment option can be modeled as a call feature or as an option such…
The discussion interprets a claim that hedge funds can ease collateral pressures by deploying liquid collateral and transforming illiquid assets. It connects that flexibility to differences between hedge funds and traditional asset managers, including limits…
The document asks how to value the first floating coupon of a fixed-to-floating interest rate swap when its SOFR observation has a ten-day lookback and the coupon period has begun, but its fixing is still in the future. The specific question is how to…
The document gives an intuitive account of the typical trade-off between option gamma and theta. A long option position has positive gamma: after delta hedging, it can benefit from sufficiently large moves in either direction. That convex payoff has a cost,…
The document compares the payoff of a year-on-year inflation swaplet, based on the ratio of two CPI levels, with a total return swaplet based on an asset price ratio. Although the payoffs have a similar form, their models need not produce the same convexity…
The document discusses why a finite-difference estimate of option theta may not match a market data provider’s reported value. A finite difference estimates the change in option value as time advances, divided by the time increment. The scale of the result…
The discussion compares two ways to value the P&L of a foreign exchange forward: tracking the change in the forward rate, and valuing the future currency cash flows with discount factors and converting them at spot. The response says these methods agree when…
The note derives how call and put time values relate under put–call parity. Starting with the usual decomposition of each option into intrinsic value and time value, substitution into parity shows that the call’s time value exceeds the put’s by the strike…
The document raises a numerical issue in Monte Carlo valuation of European calls and puts on the same stock. Under standard simulation, each option value is estimated by averaging its payoff over simulated underlying paths. With a finite sample, the…
The document explains why a vanilla option’s implied volatility is not, by itself, a reliable way to price a knock-out barrier option with a rebate. Market implied volatility is defined through the Black–Scholes formula for a vanilla contract. A volatility…
The document surveys developments beyond the classic Black–Scholes and binomial option-pricing models. It describes extensions that add stochastic volatility, stochastic interest rates, credit risk, dividends, local volatility, jumps, or GARCH dynamics. It…