Research

The intellectual foundation of Factorwork.

Factor investing and tax-aware portfolio management are both well-studied disciplines. Here we share the academic and practitioner work that informs how we build.

Factor investing

Why factors persist

The evidence for systematic factor premia — value, momentum, profitability, low volatility — spans decades and geographies. Fama and French's foundational work established that exposure to value and size explains a significant portion of cross-sectional return variation. Jegadeesh and Titman documented momentum in 1993; it has survived out-of-sample. The debate is not whether factors exist, but whether they can be harvested net of costs. Factorwork is built around that constraint.

Tax-aware investing

The tax drag problem

A 2020 Vanguard study estimated that tax-managed equity strategies can add 1–2% annually in after-tax returns relative to tax-oblivious equivalents — compounding dramatically over a 20-year horizon. The mechanism is straightforward: deferring realization of gains, harvesting losses to offset gains elsewhere, and differentiating short-term from long-term treatment. The challenge is doing this without drifting materially from the intended factor exposures. That tension — between tax efficiency and factor fidelity — is the core engineering problem Factorwork solves.

Portfolio construction

Optimization under real constraints

Mean-variance optimization in its classical form is fragile: small changes in expected return estimates produce large swings in portfolio weights. Practical implementations constrain turnover, impose position limits, and incorporate transaction costs explicitly. For taxable accounts, the cost function must include embedded gain realization. Factorwork's optimizer treats tax cost as a first-class constraint alongside tracking error and turnover — not a post-hoc adjustment.

Key references

Fama, E. F. & French, K. R. (1993)

Common risk factors in the returns on stocks and bonds

Journal of Financial Economics, 33(1), 3–56

Jegadeesh, N. & Titman, S. (1993)

Returns to buying winners and selling losers: Implications for stock market efficiency

Journal of Finance, 48(1), 65–91

Novy-Marx, R. (2013)

The other side of value: The gross profitability premium

Journal of Financial Economics, 108(1), 1–28

Israel, R., Jiang, S. & Ross, A. (2018)

Craftsmanship alpha: An application to style investing

Journal of Portfolio Management, 44(2), 23–39

Vanguard Research (2020)

Tax-loss harvesting: A portfolio and wealth planning perspective

Vanguard Research Paper

Berkin, A. L. & Ye, J. (2003)

Tax management, loss harvesting, and HIFO accounting

Financial Analysts Journal, 59(4), 91–102

See how the research becomes software.

Factorwork translates these ideas into a production-grade optimization engine for RIA portfolios. Request early access to see it in action.

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