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.
8,116 documents
The discussion concerns differences between futures option quotes shown in a broker's trading platform and those delivered through its Excel interface. A user reports that the displayed ES quote can diverge from the API feed and then align again after…
The document explains why some options markets, especially over-the-counter foreign exchange, quote implied volatility by delta rather than by strike. In these markets, available strikes are not fixed and prices may not be directly quoted. Delta provides a…
The answer treats a future implied volatility surface as a conditional modeling problem. In the direct approach, simulate outer paths under a calibrated model; at a future state, launch an inner Monte Carlo from that state, price options across strikes and…
The discussion explains why the payoff of a payer swaption cannot generally be inferred from the terminal swap rate alone. If the swaption finishes in the money, its value is the present value of the fixed leg annuity, whose payments must each be discounted…
The document distinguishes a forward rate over a future period from the fixed rate on a swap that begins in the future and spans the same tenor. The forward rate is derived from discount factors at the period’s endpoints, while a forward starting swap rate…
The document explains why an increase in a dividend expected before a European call’s expiration generally reduces the call’s value. A dividend payment transfers value from the company to shareholders, so the stock price is expected to fall by the additional…
The document describes two ways to estimate an option volatility surface for an asset with no listed options, using a more liquid, correlated asset as a reference. A practical rule of thumb maps the reference asset’s at-the-money implied volatility through a…
The document considers a European payoff equal to the larger of a linear upside outcome, the underlying price minus a constant, and a linear downside outcome, another constant minus the underlying price. It proposes representing the payoff as a fixed amount…
The discussion compares buying weekly deep in-the-money calls and rolling them each expiration with buying a call about a month out. It asks which approach minimizes time value paid per day, assuming implied volatility stays constant. One response suggests…
The document examines a common tension in options practice: Black–Scholes is often treated as a way to express prices through implied volatility, even though its assumptions do not fully describe markets, while its Greeks are still used to measure portfolio…
The document considers hedging a short put when short selling its underlying stock is prohibited. It explains that using a negatively correlated stock can reduce exposure, but generally cannot replicate the put exactly: the underlying and substitute stock…
The document asks whether regression approaches beyond Andersen’s method and Longstaff–Schwartz can estimate exercise decisions for Bermudan claims. It frames the price as an optimization over exercise times and explains that these methods estimate an…
The document explains futures-style settlement for options on futures and contrasts it with the stock-style premium payment described for US options. Under futures-style settlement, opening the position requires no initial cash premium transfer. Instead,…
The question asks how to plot a European option’s value across many underlying prices without rebuilding the QuantLib example for each value. The accepted response illustrates setting up a vanilla option with an analytic European pricing engine, attaching…
The document asks whether the Black model’s N(d2) represents the risk-neutral probability that a vanilla caplet finishes in the money, and what probability applies to a floorlet. The response interprets the question as one about the probability of a digital…
The document considers whether investors with a persistent strategic allocation, such as a balanced equity and bond portfolio, should add option based protection against severe losses. Its motivation is asymmetric: a large loss may threaten an investor’s…
The document explains delta as the sensitivity of an option’s value to a change in the underlying asset’s value. A quoted 50 delta corresponds approximately to a 0.5 change in option value for a one-unit change in the underlying, making delta useful for…
The document examines how an option’s moneyness affects the interest cost of carrying a delta hedge. The accepted explanation isolates financing interest from other components of hedging, such as theta and gamma costs. Under that framing, the cash interest…
The document asks why a Brownian-motion stock model can have a unique risk-neutral measure despite having infinitely many possible states and only one stock. It presents two explanations: completeness allows traded claims to determine the measure, and…
The document answers whether to use an underlying asset's volatility or each option's implied volatility when calculating delta or vega across strikes. It recommends using the implied volatility associated with the option's strike and expiry, reflecting the…
The document surveys empirical ways to estimate implied volatility across option strikes. It describes spline or piecewise polynomial fits, parabolic parameterizations, and Edgeworth expansions. A typical workflow selects reliable market volatilities,…
The exchange investigates an unevenly choppy implied volatility smile produced by Monte Carlo pricing of swaptions under SABR with beta below one. It describes simulating forward rates and volatility with Euler steps, estimating option prices across strikes,…
The document asks whether Vega-Vanna-Volga methods are used beyond foreign exchange derivatives and why they are common in FX. The response connects FX risk-reversal asymmetry to the possibility of central-bank intervention around exchange-rate levels. It…
The document introduces volatility dispersion trading through a position that sells at-the-money straddles on an equity index and buys straddles on its component stocks. It asks how the payoff of this combination relates mathematically to implied correlation…