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20,364 dokumenter
The document asks how to construct the tangent portfolio when short selling is prohibited. With short sales allowed, it gives the familiar solution proportional to the inverse covariance matrix times expected excess returns, then normalizes the risky-asset…
The document poses a question about how expected asset prices can be equal under the physical probability measure, while the expected value of the more volatile asset is lower under the risk-neutral measure. It asks whether this relationship can be proved or…
The document asks whether stock exposure to market, value, or momentum factors should be estimated using returns during factor drawdowns, since those losses may be linked to factor risk premiums. It also raises the estimation challenge: crash periods offer…
The document explains the law of one price in a single-period trading model. Its central idea is that portfolios with identical payoffs should have identical current prices. This principle supports pricing a European option by constructing a portfolio of…
The document asks whether American and European puts should have the same value because they share the same terminal payoff, and what it means for an American option holder to exercise optimally. The replies clarify that matching terminal payoffs do not…
The document applies the concept of predatory trading to GameStop's 2021 episode. Predatory trading can occur when traders exploit or intensify another investor's need to reduce a position, worsening price moves and liquidation outcomes. In the response,…
The document explains the role of conversion factors in U.S. Treasury futures, where eligible deliverable notes and bonds can differ in coupon and accrued interest. A factor is set when a contract is introduced and remains fixed through expiration. It…
The document asks what return observations are needed to calculate buy-and-hold abnormal returns (BHAR) over a long event window. The example concerns an event in mid-December 2017 and a window extending from just before the event through twelve months…
The document asks how to interpret a forward rate for a future period when the rate is observed today. It points out that the current forward rate is generally not the real-world expected future rate, even though an expectation relationship holds under the…
The document examines a claim that stock gains since 1993 occurred entirely overnight and that high-volatility stocks earn positive overnight returns followed by intraday reversals. The accepted response disputes the strength and reliability of these…
The document explains why a delta-gamma-theta estimate can differ from an option’s actual price change when the underlying price moves substantially. The approximation combines the first-order delta effect and second-order gamma effect of a stock-price move…
The document asks whether a one-factor Hull–White interest-rate model can price a European swaption that includes a floor on its floating leg while matching both swaption volatility and LIBOR volatility. The response says that fitting the floor or cap market…
The document explains why a Treasury futures conversion factor should not be treated as a general estimate of a deliverable bond’s current price. The factor is based on a standardized 6% yield convention, while the question’s proposed alternative would vary…
The note explains how practitioners should choose finite-difference bumps when calculating time-sensitive option Greeks and related risk measures. A bump should be large enough to avoid numerical noise yet small enough to represent the sensitivity of…
The discussion considers whether tree and finite-difference methods can price convertible bonds whose call, put, or conversion-reset rules depend on past stock prices and allow early exercise. The central method is to add auxiliary state variables that…
The note explains why the 30/360 day-count convention does not create a risk-free profit across January 30 and 31. Under the convention described, accrued interest is unchanged on those dates: a buyer owes the same accrued amount on either day, so holding…
The document asks why a manually calculated Sharpe ratio differs from the value shown by TradingView for a backtest with six trades. It provides a short series of eight daily profit observations, including both positive and negative values and several…
The document examines a proposed test of whether empirical price data follow an Ornstein-Uhlenbeck (OU) process. The described procedure estimates OU parameters by maximum likelihood, simulates a new path using those estimates, then fits the OU model again…
The document presents a workflow for forecasting stock volatility with a GARCH(1,1) model through R’s rugarch package called from Python with rpy2. It calculates daily log returns, fits a Student-t model to returns scaled as percentages, reserves a final…
The document asks why formulas connecting local volatility to implied volatility appear to give zero volatility when the underlying price equals the strike. That apparent result would make the equations seem unusable for at-the-money options, and values near…
The document addresses the sign of interest rate sensitivity, or rho, for call and put options. It identifies a likely typographical mistake in a cited book: under the standard setup discussed, call rho is positive and put rho is negative. The explanation…
The document separates three related ideas that are often conflated in financial modeling. Standard deviation describes the spread of outcomes around a mean, while volatility commonly denotes the diffusion parameter in a geometric Brownian motion model and…
The document compares a six-month Eurodollar futures contract with a forward contract at the same quoted rate. Its main pricing distinction is daily marking to market: futures gains and losses must be invested or funded as rates move, while a forward…
The document considers whether buying a CADUSD put and selling a USDCAD call could create an arbitrage because their quoted premiums and payoffs appear to leave a net credit. The question highlights that the currencies are inversely related and argues that…