Designing a robust portfolio requires considerable expertise, data, and experience. And while there are plenty of published articles that can guide how you build your portfolio, they are not investment solutions by themselves. Wei Dai is the Head of Investment Research and Vice President at Dimensional Fund Advisors, and she joins us today for a comprehensive and informative conversation on portfolio design for higher returns. Her background includes a Doctor of Philosophy degree in Statistics, Operations research, and Financial Engineering from Princeton. She has also earned a bachelor's degree in mathematics and applied mathematics from Zhejiang University. Her work has been published in multiple journals, including The Financial Analysts Journal. She has also collaborated on articles with esteemed figures such as Professor Robert C. Merton and Robert Novy-Marx. In our conversation with Wei, we explore the contents of these articles, key findings from research conducted by Dimensional Fund Advisors, and how they are implementing this knowledge in their portfolios. We discuss the fundamental aspects of portfolio design, like expected return, risk, and costs, with Wei providing a detailed breakdown of each subject. There’s a lot to be learned from today’s conversation, and while things get pretty technical, you are in very capable hands! Tune in for a fascinating dive into the latest research on portfolio design and much more.   Key Points From This Episode:   (0:03:37) The main risk premiums that Dimensional Fund Advisors target in their portfolios. (0:05:42) How long-term drivers of returns vary across different regions: an overview of the tests and outcomes they’ve seen at Dimensional Fund Advisors. (0:07:15) Unpacking whether the value premium differs from the profitability premium across regions; why it makes sense to be globally diversified. (0:08:57) Typical approaches to a multi-premium strategy in a portfolio: a rundown of the three approaches they take at Dimensional and the trade-offs between each. (0:13:44) How they evaluate portfolios at Dimenstional: the benefits of taking a holistic, integrated approach, and instances where that doesn’t make sense. (0:17:24) Weighting schemes: Dimensional’s approach to assigning individual security weights to achieve the desired level of exposure and how investments factor into weights. (0:26:46) Advice on how investors should decide whether to currency hedge their foreign asset exposures, and insights on how to approach currency hedging. (0:30:42) Premium timing: Why timing exposure to premiums is so tempting; parameters that must be defined to implement timing strategies; and which strategies worked in their research. (0:39:21) Valuation ratios: why it theoretically makes sense that they would be related to differences in expected returns and why they aren’t useful in timing premiums. (0:42:11) An overview of the main implications for pursuing premiums that arise from Dimensional’s research. (0:44:10) Diversification and how to improve your odds of capturing return premiums. (0:46:38) The tradeoff between concentration and expected returns, and defining the optimal balance. (0:49:06) What investors should look for when choosing a systematic investment manager, why not all systematic strategies are created equal, and Dimemsional’s approach. (0:52:52) The downsides of performance fees, specifically for systematic managers and what it was like writing a paper with Robert Merton. (0:57:41) How short-term reversals differ from momentum, ways that reversals are related to liquidity, and how reversals vary across different stocks. (01:03:12) The ways that Dimensional is implementing this knowledge in their portfolios; how their ideas go from research to publication to implementation. (01:08:18) What sets Dimensional apart, and the value that they add, despite their research being available online.   Links From Today’s Episode: Rational Reminder on iTunes — https://itunes.apple.com/c