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.
5,922 documents
The document asks how Cover’s universal portfolio algorithm compares with two simple allocations: a constant-relative-proportions portfolio that rebalances to equal weights, and a buy-and-hold allocation that initially divides wealth equally across assets.…
The document introduces the maximum diversification portfolio objective, defined as the weighted sum of asset volatilities divided by portfolio volatility. The numerator uses asset weights and individual volatilities; the denominator depends on the…
The discussion addresses how to calculate Sharpe ratios for historical portfolios and compare them with figures published by fund companies or financial portals. It asks which risk-free rate to use and how to align return and volatility calculations. The…
The document addresses how to compare portfolio performance from quarterly observations over a common sample period. It converts the cumulative return into a per-quarter compounded rate using the number of observations, then annualizes that rate by…
The document gives two ways to form a bond portfolio with matched dollar BPV, making the portfolio duration-neutral while retaining positive convexity. One example pairs a lower-coupon Treasury with a higher-coupon Treasury of a nearby maturity. The stated…
The document presents a one-period market with three possible states and two assets: a risk-free asset and a risky asset whose returns differ by state. It asks how to prove that no arbitrage exists and how to describe the family of state price vectors when…
The document examines whether a cross sectional mean reversion strategy can replicate an equity index using a subset of its components. The proposed signal buys stocks whose returns lag the universe and shorts those that outperform. The response explains…
The document asks how to estimate annual mean returns and a four-asset covariance matrix from quarterly observations. It states the correct compounding relationship: an annual return is the product of the four quarterly gross returns minus one. The proposed…
The document asks whether investors can build a diversified portfolio with higher expected returns by combining risky investments whose returns are uncorrelated. It frames the question with an asset-pricing relation in which price depends on expected future…
The document distinguishes two definitions of tracking error and explains how each relates to a portfolio’s beta against its benchmark. When tracking error is the volatility of active returns—the portfolio return minus the benchmark return—a beta of one is…
The document outlines a practical workflow for stock factor investing: define an investible universe, collect and process factor data, then rank or score securities. It describes several ways to turn scores into holdings, including selecting a subset and…
The document explains how to estimate alpha for many funds at once using the Fama–French three-factor model. It arranges each fund’s returns in a separate column, subtracts the risk-free rate to form excess returns, and constructs a shared factor matrix with…
The document compares forecasting each security’s return and combining the predictions with forecasting a portfolio return directly. Its central point is that, for linear return models, portfolio characteristics or factor exposures are weighted averages of…
This document raises a portfolio-attribution question: how to extend geometric Brinson-style analysis so that overweight and underweight positions in individual securities and groups can be examined separately. It distinguishes the allocation component,…
The document explains an example comparing the future value of pre-tax and post-tax retirement contributions. It starts with a dollar contribution, a fixed tax rate, an annual return, and a retirement horizon. The post-tax amount is compounded directly; the…
The document asks whether portfolio concentration by region or industry can serve as a proxy for general wrong-way risk (GWWR). It defines GWWR as a relationship in which broad market factors both increase exposure and raise a counterparty’s probability of…
The question asks whether Markowitz portfolio construction should use closing prices or dividend-adjusted prices when estimating a minimum-variance portfolio, an optimal risky portfolio, and an efficient frontier. The answer frames the choice around how the…
The document asks how to use five years of weekly returns for three asset classes to find a minimum-variance portfolio and plot an efficient frontier in Excel. It notes that a simple two-asset weight table becomes cumbersome as the number of assets grows,…
This discussion interprets a corporate bond portfolio’s relative weights across short, medium, and long maturity buckets alongside credit-curve movements. Overweight positions in shorter and intermediate buckets, with an underweight in the long bucket, are…
The document considers portfolio rebalancing when expected-return signals refresh quarterly but risk estimates update daily. At an interim rebalance, prices have moved while the original alpha forecasts grow stale, creating uncertainty about whether to…
The document explains that whether to include an intercept in a return regression depends on the hedge objective. Regressing the returns of an asset on other assets produces hedge weights, but the intercept changes what the fit is optimizing. For minimizing…
The document considers comparing two portfolio strategies when Monte Carlo simulation produces a collection of Sharpe ratio estimates for each strategy. The response uses an approximate normal sampling distribution for an estimated Sharpe ratio, with…
The document discusses how to assess whether an asset pricing model needs an additional factor, using the size factor in a three-factor model as an example. A factor’s average return alone does not determine whether it can be removed: dropping it can change…
A correlation matrix may show small negative eigenvalues because of floating-point rounding or estimation problems. The document does not supply a universal cutoff for deciding whether a negative value is merely numerical noise. Instead, it points to…