The document compares ways to estimate value at risk for a call option. If historical prices for the option are available, an analyst can calculate returns over the chosen horizon and estimate VaR from a tail percentile. For a current option without a usable…
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8,116 documents
The discussion compares ways to fit implied volatility skew across strikes for a single option maturity. A quadratic polynomial is raised as a simple alternative to higher-order polynomial fits, but the responses focus on parametric distribution approaches…
The answer explains a route from stochastic future volatility to strike-dependent implied volatility. It writes a vanilla option value as an expectation over possible future realized volatilities, or equivalently as an average of Black–Scholes prices…
The document asks why model-free implied volatility measures such as VIX are offered for major equity indices and only a small number of individual stocks. The accepted response adds that similar indices also exist for gold, silver, and oil, showing that the…
The document poses an apparent contradiction in the Black–Scholes model. As volatility rises without bound, the probability that a geometric Brownian motion finishes above the strike tends toward zero, which seems to imply a worthless call. Yet the…
The discussion considers whether options trade directly on the MSCI World index and where researchers might obtain broad international options data. Responses suggest that a single database covering all exchange-traded instruments worldwide is not available,…
The document examines an FX option whose payoff is settled in the currency of the underlying rather than the usual domestic currency. It first sketches a Black–Scholes setup for an exchange rate, then changes the payoff through the currency conversion and…
The discussion compares at-the-money payer swaptions with different expiry and underlying swap terms: one-year expiry on a ten-year swap and ten-year expiry on a one-year swap. It explains that expiry affects option value through volatility accumulated over…
The document explains why an American call or put, with the other contract and market assumptions held fixed, is worth at least as much when its maturity is extended. The central argument is based on exercise flexibility: any stopping time available before…
The response cautions that an expected end to quantitative easing does not automatically imply falling Treasury futures prices or a profitable long put position. If a policy change is widely anticipated, markets may already reflect it. The author also points…
The document discusses the two-dimensional term structure of lognormal implied volatility for European swaptions, varying by option expiration and underlying swap tenor. It describes a typical pattern in which volatility may rise over the shortest…
The note explains how to translate option sensitivities into approximate dollar gains or losses for specified changes in the underlying price and implied volatility. It defines delta and vega as changes in option value for unit changes in their respective…
The note explains the theoretical replication of a variance swap using out-of-the-money options across strikes. Its fair variance is expressed as an integral of put prices below the forward and call prices above it, weighted inversely by squared strike.…
The document discusses why American options on illiquid underlyings are difficult to price: when the underlying share value is poorly known, option valuation is correspondingly uncertain. One answer recommends scenario-based risk and reward analysis, similar…
The document explains that a basic geometric Brownian motion assumes constant drift and volatility, so company fundamentals are not directly represented. To include fundamental information, an analyst would need a separate model translating it into…
The document examines a three-strike call position: buying calls at the lower and higher strikes while selling two calls at the middle strike, all with the same expiration. It asks why the position can have a negative value at inception. The replies point to…
The document clarifies why finite-difference descriptions for option pricing may appear to reverse the usual pairing of explicit schemes with forward time differences and implicit schemes with backward differences. It explains that explicit and implicit…
The document describes how a swaption trader can move from an at-the-money implied volatility surface to prices for options struck away from the money. The answer says that desk models commonly add parameters for the volatility smile and skew: these capture…
The document describes a numerical problem in recovering probability densities with the COS method. The author compares truncation intervals built from cumulants through orders two, four, and six, and reports that the resulting densities shift substantially…
The note answers a request for data on structured products, including statistics by product type, issuance count, and location. It points readers to a regularly updated, freely available source focused on the United States. This makes the response useful as…
The note gives the Black–Scholes put-call parity relation for asset-or-nothing options. It expresses the asset-or-nothing put price as the prepaid underlying value less the corresponding call price, then substitutes the call pricing formula to obtain the put…
The document derives the sensitivity of European option prices to the risk-free interest rate in the Black–Scholes model. Differentiating the call price and simplifying with the relationship between the normal density values at d1 and d2 produces call rho as…
The document asks whether volatility measures calculated from intraday price data can help predict close-to-close squared returns. The intended use is estimating the profit and loss of a gamma scalping strategy that trades once daily, with trading assumed to…
The document asks whether a call spread’s value plotted against the underlying price must be symmetric before expiration. The response distinguishes the payoff at maturity from the option’s value earlier in its life. At maturity, the spread’s payoff may…