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 document explains how foreign exchange volatility surface expiries are dated relative to currency settlement conventions. It distinguishes weekly tenors, which are counted from the current date, from monthly and yearly tenors, which are counted from the…
The document addresses why a put-call ratio may convey sentiment even though every options trade has both a buyer and a seller. Its answer focuses on which side is more motivated to initiate a position: it cites a claim that put buyers may be especially…
The document asks how to interpret VVIX, an index representing the market’s expected volatility of VIX, and compares two informal explanations. One describes volatility of volatility as uncertainty about how the size of daily price moves may change. The…
A Bermudan option can be exercised on several specified dates. Its value is not generally the highest value among European options with matching individual exercise dates. Taking that maximum amounts to choosing a single exercise date at the outset and…
The document addresses unstable Heston model calibration: very large mean-reversion and volatility-of-volatility parameters can fit a volatility surface well even when the values lack a plausible market interpretation. It notes that stochastic-volatility…
The document explains how to read implied volatility quotes for a one-year-into-five-year SOFR swaption under Bachelier and Black conventions. In the normal model, a quoted volatility of 136 corresponds to a one-year standard deviation of about 1.36…
This document discusses which price series should be used to estimate volatility for the Black model and whether volatility needs to be annualized. The responses emphasize matching the volatility estimate to the instrument used for hedging: a hedge based on…
The document examines the Greeks of a forward variance swap built from two spot-starting variance swaps. It questions how the position can have approximately zero dollar gamma and declining vega while still carrying theta. The response distinguishes model…
The volatility smile records how market implied volatility varies across option strikes. The document explains that reproducing this pattern is a practical test of an option model: the smile is a widespread market feature, observed across asset classes, and…
The document discusses ways to improve finite difference methods for solving the Black-Scholes equation, with attention to accuracy, speed, and stability. Its main recommendation is to transform the equation into the heat equation, which has simpler…
The document considers why a leveraged fund might hold a cash bond to obtain interest-rate exposure when an OIS swap could provide similar sensitivity. It does not identify a universal pricing advantage when the instruments are fairly priced. Instead, the…
The document describes a Monte Carlo implementation of the Heston stochastic-volatility model, using an exponential stock-price step and an Andersen moment-matching update for variance. The author observes that simulated variance trends downward when…
The document reports a numerical comparison between an adjusted Kirk approximation and the Bjerksund–Stensland spread option model. The author implements both formulas, adds a weight for the second spread leg, and includes call and put calculations. Across…
The response argues that public exchange option volume and call-put ratios cannot reliably establish whether dealers are net buyers or sellers of single-name options. Much options activity occurs through private over-the-counter trades, which are not…
The document poses three questions about pricing an American contingent claim (ACC): how to decompose its discounted fair value, why the matching European claim should not be worth more, and when the two prices coincide. The supplied partial argument…
The document clarifies that risk-neutral valuation applies to European-style derivatives whose maturity payoff is measurable and integrable, whether that payoff depends only on the terminal asset price or on the path taken. With constant interest rates, the…
The document explains why an option’s realized gamma PnL depends on the actual movement of the underlying, while the implied volatility used to price and mark the option is a model input. Under a fixed-volatility model, an Ito expansion attributes changes in…
The document discusses how OTC FX option quotes are organized around standard expiries and delta-based volatility quotes, while positions can age into non-standard dates. Responses explain that off-grid pricing depends on the client or dealer context, trade…
The document clarifies how to calculate the profit of a hedged stock position that combines ownership of a share with a put option. The stock contributes its terminal value minus its initial purchase price, while the put contributes its payoff at expiration…
The document discusses how to update the damping parameter in Levenberg–Marquardt calibration of the Heston stochastic volatility model. The question compares a cited Heston calibration procedure, which raises damping after rejected steps but leaves it…
The document investigates why a finite-difference Black–Scholes engine in QuantLib can return a different theta for an option priced from a Black variance surface than from a constant volatility equal to the surface’s volatility at that strike and expiry. In…
This exchange addresses how to obtain historical trade counts for individual stocks and other instruments, and how to construct a count series when a ready-made dataset is unavailable. One response points to Interactive Brokers historical bar data, where a…
The document explains why, all else equal, a callable bond can be worth more to its investor when its call price is higher. One answer compares the embedded call feature to a put-like protection: with a higher call value, interest rates must fall further…
The document asks why American options, which allow exercise at any time up to expiry, receive attention when actual trading and exercise occur discretely. It contrasts them with Bermudan options, where exercise is available only at specified dates, and…