The Rational Reminder Podcast

Elroy Dimson, Cambridge finance professor and co-creator of the long-run DMS global returns dataset, guides a tour of financial history. He recalls building century-spanning data, exposes biases that inflate past returns, and explains why 20th-century equity gains surprised many. He also covers global diversification, surprising winners like railways, and how economic growth does not automatically mean higher stock returns.

Michael Kothakota, PhD in personal financial planning and founder/CEO blending academic research with advisory practice. He outlines a mathematical framework for interdependent integrative financial planning. Short takes cover why traditional models fail, how priorities and time shape decisions, multi-objective optimization, dynamic sequential choices, and when integration adds real value.

They unpack how mega IPOs like SpaceX or OpenAI could force index funds to buy newly listed shares and why that matters. They discuss why newly public stocks often underperform and how index rules and free float shape inclusion and weights. They explore research on fast-track inclusion, low-float risks, and alternative indexing approaches. The conversation focuses on market structure, rebalancing effects, and practical trade-offs for investors.

Timothy Edwards, Managing Director and Global Head of Index Investment Strategy at S&P Dow Jones Indices, explains the SPIVA scorecard and how it compares active funds to benchmarks. He discusses survivorship bias, why most active funds underperform over time, differences between equity and bond markets, index rebalancing and IPO inclusion, and how concentration affects indices.

A deep dive into the 1993 paper that reshaped asset pricing and introduced the Three-Factor Model. They discuss why market beta alone falls short and how size and value factors changed investing. Conversation covers how factors are constructed, the rise of the factor zoo, and practical ways investors access factor strategies today.

Patrick Adams, an MIT PhD candidate studying asset pricing and household finance, explains how income risk, liquidity limits, and consumption commitments reshape optimal investing. He discusses forced selling in crashes, tax‑data evidence that high earners sell into downturns, why households move into fixed income, and a lifecycle model showing conservative stock allocations for working‑age investors.

A skeptical look at private equity, credit, and real estate and why their smooth returns may be misleading. They unpack illiquidity, valuation opacity, gated funds, and fee complexity. Discussion covers retail distribution risks, manager selection challenges, secondary-market discounts, and how private-market structures can hide real volatility.

Eduardo Repetto, CIO of Avantis Investors with a background at Dimensional, and Caitlin Ebanks, CIBC ETF strategist, discuss Avantis’ new Canadian ETF lineup. They cover product design, fee discipline, direct security ownership versus fund-of-funds, the new CAGE asset-allocation ETF, implementation details like turnover and tracking error, and how these funds aim to make factor investing simpler and more accessible.

Shelley Antoniewicz, ICI chief economist who studies who invests in index funds. Jim Rowley, Vanguard research leader on index implementation and myths. Tim Edwards, S&P DJI strategist on index history and concentration. They discuss 50 years of index investing, market concentration, index mechanics, ETF trading and implementation, and how indexing has shaped fees and investor choice.

James Choi, Yale finance professor known for practical household finance research, presents a spreadsheet-based shortcut to classic lifecycle portfolio choice. He explains Merton’s formula, how human capital often acts bond-like, the roles of wealth and risk aversion, transitory versus permanent wage risk, and how simple rules like 100-minus-age compare to his approximation.