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 addresses whether missing accounting observations in Compustat or CRSP should be replaced with zero or removed from a dataset. Its guidance is to use judgment and be cautious: zero can be nonsensical for some fields, while alternative…
The document considers whether minute-level data for large NYSE stocks can reveal if a price move came from one participant or from many smaller orders. Its central lesson is that reliable attribution is difficult because a large trader may conceal activity…
The document explains why a simple interest-rate-differential formula may fail to match observed three-month FX forward points. It identifies cross-currency basis as the key market adjustment that emerged prominently after the global financial crisis. The…
The document asks how computational cost scales for standard mean-variance portfolio optimization, whether minimum-variance portfolios are easier, and what runtimes or faster alternatives to expect. It characterizes MVO as a quadratic program and gives a…
The document asks how to define a stock’s beta relative to a market proxy such as SPY, and whether beta as a covariance-to-variance ratio equals the slope from a regression of stock returns on benchmark returns. It then considers hedging a long-short stock…
The document derives a lower bound for a European put on a non-dividend-paying stock by comparing two portfolios. One portfolio holds the put and one share; the other holds a zero-coupon bond that pays the strike at expiration. At maturity, the put-stock…
The document asks how a delta-hedged portfolio of two options leads to a Black–Scholes pricing equation, including a term for the underlying asset’s market price of risk. It writes the portfolio as one option minus a delta-scaled position in another, then…
The document questions whether a standard GARCH model’s constant conditional mean for log returns is appropriate when volatility changes. For normally distributed log returns, it notes that the conditional expectation of the simple gross return depends on…
The document presents a question about applying the Johansen procedure to oil and corn price series after unit-root tests suggest both are nonstationary. It shows example eigenvalue and trace test statistics alongside critical values, then asks how to…
The document clarifies whether market makers must trade when they are the only participants showing orders. It distinguishes designated market makers, whose exchange rules may require them to maintain two-sided quotes within a specified width for a certain…
The document considers fitting an implied-volatility curve to intraday option observations, where data become sparse and variable at extreme out-of-the-money strikes. The question is whether unusual observations can be discounted and whether option-market…
The document asks whether a closed-form valuation exists for an American down-and-out call whose principal amortizes linearly with elapsed time if the option is knocked out. It frames the payoff as a possible time-dependent rebate and compares the problem…
The document derives a self-financing replicating portfolio for a European put in a Black-Scholes market with a risky asset and a deterministic bank account. Applying Itô’s lemma to the option value and matching the diffusion terms identifies the risky-asset…
The discussion covers two linked choices when calculating a Sharpe ratio from monthly returns: selecting a risk-free return that matches the measurement horizon and converting the ratio to an annual scale. One answer suggests using a short-term Treasury rate…
The document explains how to build and plot a Heston model volatility surface using Python QuantLib. The example creates a Heston process from spot, flat risk-free and dividend curves, and model parameters, then wraps it in a Heston model and passes it to a…
The document asks how swap rates relate to a textbook par-rate calculation and why market participants quote spreads against Treasury or swap curves. The response focuses on quoting conventions rather than deriving the swap rate formula. Historically, US…
The document considers how much historical data to use when monthly portfolio rebalancing is based on Sharpe-ratio or mean-variance optimization. It does not identify a universally suitable window. One response emphasizes that expected returns and volatility…
The document explains a Monte Carlo check for an implementation of Dupire local volatility. Simulated underlying paths use the local volatility evaluated at the current simulated spot and time, with the process initialized at the market spot. For each…
The document asks for a historical catalog of long-term support and resistance levels, using EUR/USD as an example. It presents price zones alongside qualitative strength ratings and the year or period associated with each level. The example includes levels…
The note clarifies that calling an instrument balance-sheet intensive does not simply mean that it requires a large initial cash investment. The meaning depends on the desk’s accounting and regulatory context. For a bank market-making desk, balance-sheet…
The note explains a market convention for describing the right side of an implied volatility smile as call skew, even though put-call parity links those prices to in-the-money puts. The answer suggests that traders often build the smile from at-the-money and…
The note compares delta choices for hedging short-dated at-the-money options in an index dispersion trade, which pairs long single-stock variance with short index variance. It explains that using Black–Scholes delta with the option’s initial implied…
The document compares risk management for retail algorithmic traders with controls at larger quantitative firms. It describes institutional safeguards as layered: risk teams may set trading exposure limits, while compliance may focus on legal and regulatory…
The document explains why the Black–Scholes call price contains two different probabilities: N(d2), the risk-neutral probability that the option finishes in the money, and N(d1), the corresponding probability under a measure associated with using the stock…