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.
20,364 documents
The document examines a bootstrap calculation for a six-month continuously compounded zero rate using bond prices, coupon cash flows, and a one-year zero rate. Its central lesson is that a shorter-maturity spot rate can be higher than a longer-maturity rate;…
The document explains a simple way to estimate an option’s future value across a range of underlying prices for a platform-style P&L chart. The proposed baseline is to reprice with Black–Scholes using the remaining time to expiry and a chosen volatility,…
The document asks how to identify the best- and worst-performing US stocks on a historical date, using percentage change as the ranking measure. The replies suggest sorting S&P 500 constituents by daily change with a market-data site or using Bloomberg’s…
The document raises the problem of selecting a risk-free rate when valuing historical option data. It notes that rates such as Treasury or constant-maturity yields, OIS, SOFR, LIBOR, and policy rates have all been suggested, and asks which benchmark fits…
The document explains how to approximate an option’s delta numerically. Delta is the derivative of the option value with respect to the underlying asset price, describing how much the option value changes for a small change in that price. When an analytic…
The document derives the covariance between two time integrals of standard Brownian motion, taken over horizons s and t. Because each integral has zero expectation, their covariance is the expected value of their product. Interchanging expectation and…
The discussion examines how missing observations can affect comparisons between observed and model-generated time series, including running RMSE. It warns that interpolation may preserve the series’ central level while understating uncertainty, and that…
This troubleshooting exchange concerns constructing an interest-rate cap in QuantLib C++. The example builds a floating leg from an Ibor index and attempts to create a cap, but runtime initialization fails because the leg has no notional. The author notes…
The question considers how a call’s value might change when stock returns have fatter tails than a log-normal model. It gives a numerical setup with zero interest rate, specified volatility and maturity, and an initial stock price equal to the strike. The…
The discussion asks how to interpret the covariance between an underlying asset and the discount factor under the risk-neutral measure, in connection with the forward–futures spread. One answer recommends interpreting risk-neutral quantities from the…
This discussion explains how option quotes on a less liquid stock can reflect both the difficulty of hedging in the underlying and the flow of customer orders. Market makers account for hedge liquidity in their bid–ask spreads and implied volatility, so…
The document addresses whether the numeraire used in the Linear Gaussian Model must first be identified as a specific traded asset, and whether defining the state process through a measure associated with that numeraire is circular. The answer distinguishes…
The document introduces approaches for judging whether a stock may be undervalued, including comparing price-to-earnings and price-to-book ratios with industry peers. Its example treats a utility company with a higher P/E than its sector as potentially…
The document explains why a rise in interest rates can increase a call option's theoretical value, despite the possibility that higher rates may weigh on share prices. In option valuation, the strike payment is made in the future, so a higher discount rate…
The document asks how to interpret the integral of a stochastic process's intensity over the interval between two consecutive arrivals. It contrasts the usual interpretation of integrated intensity as an expected event count over a fixed time window with a…
The document raises a pricing question about the embedded call feature in a callable floating-rate note. The author understands a callable bond as a straight bond combined with a short receiver swaption, and asks how to isolate or value the option component…
The document explains the inputs and calculation used by MATLAB’s PORTVAR function. Asset data are arranged with one security’s historical observations in each column, and portfolio weights correspond to those columns. If weights are omitted, the function…
The document outlines three broad approaches to credit portfolio management: structural models, actuarial or intensity models, and macro-factor or econometric models. It mentions KMV-style models and CreditMetrics as examples associated with the structural…
The document considers how to compare a fixed-income security’s price series with a US Treasury bill as a risk-free benchmark, particularly when the intended holding period is only a few days. It notes that there is no universally correct maturity to use and…
The document asks how to build a multi-year time series for a three-month futures contract while handling contract rolls. The author is concerned that prices are volatile on roll days and asks about interpolation or using calendar spreads to create…
The document distinguishes Avellaneda–Stoikov quote placement from the choice of order quantity. The model’s quoted prices respond to inventory and other model inputs, while its trade units are relative: scaling every unit by the same factor does not change…
The document asks how selecting an iron condor’s short strikes by option delta relates to changes in implied volatility. The central question is whether choosing a target delta makes the spread width adjust as volatility changes, even though the distance…
The document considers the reciprocal of a stock price modeled by geometric Brownian motion (GBM). It gives the standard GBM solution and uses the moment-generating identity for a Gaussian variable to derive the reciprocal’s mean. For initial price S₀, drift…
The document addresses which bond price belongs in a duration calculation. It defines modified duration using the derivative of price with respect to yield divided by price, and identifies that price as the dirty price, which includes accrued coupon…