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 distinguishes processes with independent increments from Lévy processes. In a process with independent increments, future increments are independent of the information available at the start of the interval; a Lévy process adds the condition…
The discussion explains why market data feeds often identify securities with ticker symbols even though symbols may be reused, and why an ISIN alone may not identify the precise price series a researcher needs. Tickers are familiar and predate ISINs, while…
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 considers which market data should anchor the short end of zero-coupon curves for Eurozone sovereign issuers outside Germany. It distinguishes interbank reference rates such as Euribor and EONIA from government borrowing rates: the former…
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 asks how to compare a forecast of three-month carry and rolldown on a five-year interest rate swap with the swap’s realized return. It cites a decomposition into the return from changes in market value, the effect of the curve point rolling to a…
The document compares over-the-counter FX forwards with exchange-traded futures, explaining why customers and banks may use the OTC market. Forwards can be tailored to a customer’s currency, amount, and delivery date, while listed futures use standardized…
The document defines a discounted stock price as the stock’s value divided by the money market account, or, with a constant rate, as the stock price multiplied by the discount factor. Under the risk-neutral measure, this discounted price is a martingale. The…
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 explains how to prepare an object accepted by the `estim_nss` function in R’s `termstrc` package, which estimates a spot curve from bond data. The key requirement is to build the package’s expected nested bond-data structure and assign it the…
The document compares Bloomberg and Reuters as market data sources for a firm considering consolidation of feeds used for derivatives and bonds. It covers pricing, infrastructure, data quality, instrument identifiers, and alternative vendors. The response…
The document asks how an efficient frontier based on expected return and Entropic Value-at-Risk (EVaR) should compare with frontiers built using variance or Conditional Value-at-Risk (CVaR). It notes that EVaR is an upper bound on VaR and CVaR, then asks…
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 derives an explicit solution for a process with a level-proportional drift and constant diffusion, starting from a specified value at time S. It applies an integrating-factor method: multiply the process by an exponential factor, use Itô’s lemma…
The document explains negative repurchase agreement rates using euro-area monetary conditions. When central bank policy rates are negative, overnight repo rates can also fall below zero. In the example discussed, a cash borrower posting German or French…
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…
The document proposes a mean–variance model for a static portfolio of assets quoted at bid and ask prices. It represents each asset’s long and short exposure as separate nonnegative variables, calculates expected returns and covariances for those positions,…
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 question asks how to choose the function in Ito’s lemma to find the differential of a process defined as the exponential of a constant times Brownian motion. The answer clarifies that the process is a function of the underlying stochastic variable,…
This exchange considers why two bonds from the same company can show sharply different Z-spreads, challenging the idea that the measure isolates issuer credit risk and should therefore be similar across the issuer’s debt. It illustrates the issue with two…
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 examines how to convert a value-at-risk estimate expressed as a log return into a dollar amount. It presents two candidate conversions: multiplying the position value by the log-return VaR, or multiplying by the exponential of that VaR minus…
The question explores whether borrowed money can fund a stock purchase whose shares are sold periodically to cover loan installments. It asks about break-even price growth, sale timing, and the return required, while proposing an installment estimate based…
The document compares two ways to estimate a current fair price for one instrument from the historical prices of a correlated instrument pair. One method multiplies the current price of the target instrument by the ratio of the two instruments’ average…