Scientific Beta

This issue examines the challenges of market concentration and offers evidence-based solutions through diversified and factor strategies. It also assesses machine learning, ESG data, single-factor design, portfolio completion, climate-focused indices, and the impact of controversial-weapons screens—providing practical guidance for building robust, future-ready equity portfolios.

This Scientific Beta supplement to P&I examines the challenges of market concentration and offers evidence-based solutions through diversified and factor strategies. It also assesses machine learning, ESG data, single-factor design, portfolio completion, climate-focused indices, and the impact of controversial-weapons screens—providing practical guidance for building robust, future-ready equity portfolios.

This Scientific Beta supplement to P&I explores key challenges and opportunities facing equity investors in an environment of extreme US market concentration.

Drawing on long-term evidence, it shows why diversified strategies are well positioned to outperform mega-caps over the coming decade and outlines practical approaches to mitigating concentration risk through multi-factor solutions.

The supplement also examines how machine learning and ESG data can contribute to portfolio construction—highlighting both their genuine potential and their limitations.

Several articles detail the design of robust single-factor strategies, including value, risk-managed momentum, and 130/30 approaches, along with a practical portfolio-completion case study.

The publication concludes with insights into building a fact-based climate strategy and navigating the performance and policy implications of controversial-weapons exclusions.