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Value Investing Strategy (Strategy Overview)
Allocations for February 2026 (Final)
Cash TLT LQD SPY
Momentum Investing Strategy (Strategy Overview)
Allocations for February 2026 (Final)
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Size Effect

Do the stocks of small firms consistently outperform those of larger companies? If so, why, and can investors/traders exploit this tendency? These blog entries relate to the size effect.

Doing Momentum with Style (ETFs)

“Beat the Market with Hot-Anomaly Switching?” concludes that “a trader who periodically switches to the hottest known anomaly based on a rolling window of past performance may be able to beat the market. Anomalies appear to have their own kind of momentum.” Does momentum therefore work for style-based exchange-traded funds (ETF)? To investigate, we apply a simple momentum strategy to the following six ETFs that cut across market capitalization (large, medium and small) and value versus growth:

iShares Russell 1000 Value Index (IWD) – large capitalization value stocks.
iShares Russell 1000 Growth Index (IWF) – large capitalization growth stocks.
iShares Russell Midcap Value Index (IWS) – mid-capitalization value stocks.
iShares Russell Midcap Growth Index (IWP) – mid-capitalization growth stocks.
iShares Russell 2000 Value Index (IWN) – small capitalization value stocks.
iShares Russell 2000 Growth Index (IWO) – small capitalization growth stocks.

We test a simple Top 1 strategy that allocates all funds each month to the one style ETF with the highest total return over a specified momentum ranking (lookback) interval. We focus on a 6-month ranking interval as often used in prior research, but test sensitivity of findings to ranking intervals ranging from one to 12 months. As benchmarks, we consider an equal-weighted and monthly rebalanced combination of all six style ETFs (EW All), and buying and holding SPDR S&P 500 (SPY). As an enhancement we consider holding the Top 1 style ETF (3-month U.S. Treasury bills, T-bills) when the S&P 500 Index is above (below) its 10-month simple moving average at the end of the prior month (Top 1:SMA10), with a benchmark substituting SPY for Top 1 (SPY:SMA10). We employ the performance metrics used for SACEMS. Using monthly dividend-adjusted closing prices for the six style ETFs and SPY, monthly levels of the S&P 500 Index and monthly yields for T-bills during August 2001 (limited by IWS and IWP) through June 2024, we find that:

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Exhaustively Timing Equity Factor Premiums

Can investors reliably time the market, size, value and profitability long-short equity factor premiums? In their October 2023 paper entitled “Another Look at Timing the Equity Premiums”, Wei Dai and Audrey Dong test strategies that time these four premiums in U.S., developed ex-U.S. and emerging equity markets. They define the premiums as:

  1. Market – the capitalization-weighted market return minus the U.S. Treasury bill yield.
  2. Size – average return on small-capitalization stocks minus average return on large-capitalization stocks.
  3. Value – average return on value stocks minus average return on growth stocks.
  4. Profitability – average return on stocks of high-profitability firms minus average return on stocks of low-profitability firms.

They time each premium separately based on each of:

  1. Valuation ratio – When the difference in aggregate price-to-book ratio between the long and short sides of a premium becomes high (low) relative to its historical distribution, switch to the short (long) side.
  2. Mean reversion – When the premium itself becomes high (low) relative to its historical distribution, switch to the short (long) side  of the premium.
  3. Momentum – When the premium over the last year becomes relatively high (low), switch to the long (short) side of the premium.

To measure historical premium distributions, they consider an expanding window of initial length 10 years or a rolling 10-year window. For switching to the short side of premiums, they consider historical distribution thresholds of top 10%, 20% or 50% (bottom 10%, 20% or 50%) for valuation ratio and mean reversion (momentum). For switching to the long side of premiums, they consider thresholds of bottom 10%, 20% or 50% (top 50%) for valuation ratio and mean reversion (momentum). They consider  monthly or annual portfolio rebalancing. The number of timing strategies tested is thus 720. For the U.S. sample, monthly returns start in July 1963 for profitability and July 1927 for the other three premiums. For the developed ex-U.S. (emerging markets) sample, premium returns start in July 1990 (July 1994). Benchmarks are returns to strategies that continuously hold just the long side of each premium portfolio. Using monthly data as specified through December 2022, they find that: Keep Reading

Comparing Long-term Returns of U.S. Equity Factors

What characteristics of U.S. equity factor return series are most relevant to respective factor performance? In his May 2023 paper entitled “The Cross-Section of Factor Returns” David Blitz explores long-term average returns and market alphas, 60-month market betas and factor performance cyclicality for U.S. equity factors. He also assesses potentials of three factor rotation strategies: low-beta, seasonal and return momentum. Using monthly returns for 153 published U.S. equity market factors, classified statistically into 13 groups, during July 1963 through December 2021, he finds that:

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Boosting Retirement Outcome via Capture of Factor Premiums

Can investors improve long-term retirement portfolio outcomes by targeting equity factor premiums in their stock allocations? In his April 2023 paper entitled “How Targeting the Size, Value, and Profitability Premiums Can Improve Retirement Outcomes”, Mathieu Pellerin investigates whether stock portfolios that target size, value and profitability factor premiums better sustain retirement spending and generate larger bequests than those holding the broad stock market. His hypothetical investor:

  • Starts saving at 25, retires at 65 and dies at 95.
  • Initially allocates 100% to stocks, at age 45 reduces this allocation linearly to 50% at age 65 by shifting to bonds, and thereafter maintains 50%/50% stocks/bonds.
  • Makes $1,042 monthly contributions ($12,500 per year, or $500,000 from age 25 to 65).
  • After retirement, withdraws (consumes) a constant annual 4% in real terms of the balance at retirement.
  • For the stock allocation, chooses either a broad value-weighted market index (CRSP 1-10) or the Dimensional US Adjusted Market 1 index that emphasizes size, value and profitability factors with low turnover.
  • Earns real annual broad stock market returns of either 8.1% (actual historical average) or 5.0% (a conservative 5th percentile of historical return distribution).
  • For the bond allocation, holds 5-year U.S. Treasury notes.

He simulates 100,000 lifecycles by, for each lifecycle: (1) extracting 70-year (840-month) real asset class return subsamples from the full histories; and, (2) applying block bootstrapping with 10-year mean block size to generate lifecycle portfolio returns. Using monthly historical returns for the specified stock/bond proxies and monthly U.S. inflation data during June 1927 through December 2022, he finds that:

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Equity Factor Performance Before and After the End of 2000

Do the widely used U.S. stock return factors exhibit long-term trend changes and shorter-term cyclic behaviors? In his November 2022 paper entitled “Trends and Cycles of Style Factors in the 20th and 21st Centuries”, Andrew Ang applies various methods to compare trends and cycles for equity value, size, quality, momentum and low volatility factors, with focus on a breakpoint at the end of 2000. He measures size using market capitalization, value using book-to-market ratio, quality using operating profitability, momentum using return from 12 months ago to one month ago and low volatility using idiosyncratic volatility relative to the Fama-French 3-factor (market, size, book-to-market) model of stock returns. He each month for each factor sorts stocks into tenths, or deciles, and computes gross monthly factor return from a portfolio that is long (short) the average return of the two deciles with the highest (lowest) expected returns. As a benchmark, he uses the value-weighted market return in excess of the U.S. Treasury bill yield. Using market and factor return data from the Kenneth French data library during July 1963 through August 2022, he finds that:

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Why EW Beats VW

Why do equal-weighted (EW) portfolios outperform their market capitalization-weighted, or value-weighted (VW), counterparts over multiple decades in various investment universes? In their November 2022 paper entitled “Why Do Equally Weighted Portfolios Beat Value-Weighted Ones?”, Alexander Swade, Sandra Nolte, Mark Shackleton and Harald Lohre analyze drivers of differences in performance between EW and VW U.S. stock portfolios over six decades. They also assess consistency of performance drivers. Using monthly returns for a very broad sample of U.S. common stocks and monthly stock factor returns during July 1963 through December 2021, they find that:

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O’Shaughnessy Micro Cap Strategy?

A subscriber, referring to a March 2016 commentary stating that “microcap stocks offer investors one of the best opportunities for consistent, long-term excess returns,” inquired about the performance of quality-value-momentum microcap strategy described therein. To assessment this strategy, we compare the self-reported annual performance of the O’Shaughnessy Micro Cap strategy (OSMC) as of June 2022 (now maintained by Franklin Templeton) to that of simply buying and holding SPDR S&P 500 ETF Trust (SPY). Using annual self-reported OSMC net returns and matched dividend-adjusted SPY returns during August 2007 through June 2022, we find that: Keep Reading

Failure of Equity Multifactor Funds?

Multifactor funds offer rules-based, diversified exposures to firm/stock factors found to beat the market in academic studies. Do the funds beat the market in real life? In his June 2022 paper entitled “Multifactor Funds: An Early (Bearish) Assessment”, Javier Estrada assesses performance of such funds across U.S., global and emerging markets relative to that of corresponding broad capitalization-weighted indexes and associated exchange-traded funds (ETF). He focuses on multifactor funds with exposure to at least three factors that are explicitly marketed as multifactor funds. Using monthly total returns for 56 U.S.-based equity multifactor funds with at least three years of data and $10 million in assets from respective inceptions (earliest June 2014) through March 2022, and total returns for matched broad market indexes and ETFs, he finds that:

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Interaction of Long-only Value and Size

Does the finding from long-short factor analysis that the value premium is stronger among small stocks than large stocks hold for long-only value portfolios? In his April 2022 paper entitled “Long-Only Value Investing: Does Size Matter?”, Jack Vogel investigates interactions between the value premium and market capitalization for U.S. and international stocks. The steps in his main analysis are to each year on June 30:

  • Group the 3,000 largest U.S. stocks by market capitalization with non-zero market value of equity into the 1,000 largest firms (large-cap) and the 2,000 smallest (small-cap).
  • Rank each group into thirds (terciles), fifths (quintiles) or tenths (deciles) based on each of: (1) book-to-market ratio (B/M); (2) earnings-to-price ratio (E/P); (3) free cash flow-to-price ratio (FCF/P); (4) earnings before interest and taxes-to-total enterprise value ratio (EBIT/TEV); and, (5) the composite rank of these four ratios.
  • Measure average monthly returns over the next year of the top ranks based on either equal weights (EW) or value weights (VW).

Using the specified accounting data and stock prices for a broad sample of U.S. firms since July 1973 and for a comparable sample of international developed market firms since January 1994, all through December 2020, he finds that: Keep Reading

Measuring the Size Effect with Capitalization-based ETFs

Do popular capitalization-based exchange-traded funds (ETF) offer a reliable way to exploit an equity size effect? To investigate, we look at the difference in returns (small minus big) between:

  • iShares Russell 2000 Index (Smallcap) Index (IWM), and
  • SPDR S&P 500 (SPY)

Using monthly dividend-adjusted closing prices for these ETFs during May 2000 (limited by IWM) through March 2022, we find that: Keep Reading

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