Shaking Up Market Thinking

If you think economics is just about supply and demand, Christopher Walker, new Assistant Professor of Economics, would like you to flip a coin and make a random guess about whether it will be heads or tails. Then, flip it again, but this time, update your guess based upon the 50-50 odds that it will land a certain way.

That’s incorporating Bayesian thinking, and Walker’s research on using new information to guide our predictions of future outcomes is changing the way economists ask their biggest questions about competition, productivity, and market behavior, from mergers and policy to individual choice and causal inference. Walker uses advanced statistical tools to build flexible models that can provide insight into how firms and consumers may behave.

Walker takes complex and sometimes messy economic models and distills them into simple, policy-relevant tools that can provide practical insights, such as whether market intervention benefits or harms consumers. His work on semiparametric methods, which apply statistical analysis in a way that balances structure and flexibility, bridges traditional econometrics and modern machine learning. Walker focuses on finding reliable ways to extract small, trustworthy insights from big, cumbersome systems.

On top of advancing his current research, Walker is looking forward to teaching a second-year PhD course. The second year of a doctoral program, he said, is a pivotal time for students to drill down on what they want to study.

“I want the students to be able to think very rigorously about economic models,” said Walker. “I also hope my class will provide a way for them to potentially innovate in their own space, whatever they end up specializing in.”

Part of what excites Walker about teaching, he said, is seeing students identify gaps in the literature and put together interesting papers based on those gaps, which is how he got started in the field of Bayesian thinking.

In addition to his own research and teaching, Walker will be diving headfirst into life at Duke Econ.

“The economics department here is fantastic and has so much diversity in their interests,” said Walker. “An important aspect of the department is that we are one unit. We're not just econometrics or theory; we’re working together to create a dialogue.”

He emphasized that the department is a place where faculty bring diverse approaches, even within the same subfields. That variety, he noted, sparks conversations that allow colleagues to share strengths and generate new ideas together. He added that faculty in applied areas value innovation, which encourages collaboration across specialties. To him, the department feels like a single, integrated unit rather than separate silos.

Walker continues to contribute new ideas to questions at the heart of how markets function and how policies shape competition. His work not only pushes the boundaries of scholarship but also provides tools for making sense of the systems that affect consumers, firms, and regulators alike.

Along with Walker, Duke Economics also hired Yingni Guo and Wendy Morrison. Chair James W. Roberts is looking forward to the way Walker and the rest of the new faculty will improve the department and Duke as a whole.

“These new faculty bring expertise in a wide variety of subfields within the economics discipline and will also bring great energy to the department and our students,” said Roberts.