08-18-2026
Many people associate economists with forecasting inflation, analyzing economic growth, or teaching in universities. Those are important roles, but they represent only part of the profession.
When I came to the Daniels School for my PhD, I expected economics to be primarily an academic discipline. While preparing a course report in Industrial Organization, I was fascinated to discover that economists were also helping companies, regulators and courts tackle real-world problems. Discovering that changed the direction of my career.
I began my postdoctoral career by teaching economics at Japanese universities, then served as an economist and merger reviewer at Japan's Fair Trade Commission and eventually entered economic consulting. Though the institutions, stakeholders and decisions were all different, the underlying challenge remained the same: understanding how people, firms and markets respond to incentives and using evidence to help make better decisions.
Consider a proposed merger. Regulators must assess whether a transaction is likely to reduce competition and harm consumers. Companies must evaluate the strategic benefits and risks. The answer requires careful analysis of customer behavior, market conditions and competitive dynamics.
In one merger case, the central question was whether two competing firms could effectively substitute for one another in the eyes of customers. That question sounds straightforward. As similar as two firms seem, careful analysis of pricing data, customer contracts and competitive behavior across multiple markets reveals just how alike they are or aren’t. Answering the question required rigorous analysis. What would happen if one firm replaced the other? How would it impact consumer behavior and current contracts?
The same principle applies in litigation. In a patent dispute, economists may be asked to assess the economic consequences of an alleged infringement. In securities litigation, they may examine whether a company's stock price decline was caused by a specific disclosure or by broader market developments. While the facts differ from case to case, the goal remains the same: identifying cause and effect in situations where uncertainty is unavoidable. Economic analysis does not eliminate uncertainty, nor does it guarantee a single correct answer. It provides a disciplined framework for separating facts from assumptions, evidence from intuition, and plausible explanations from less plausible ones. In my view, that is one of the most valuable contributions economics can make.
Today, as an economist working in Japan, I see these same analytical challenges emerging in debates surrounding artificial intelligence, digital platforms and technological innovation. These issues are often discussed as matters of technology or regulation. Yet the analytical challenge is familiar: understanding incentives, assessing competitive dynamics, and making decisions under uncertainty.
Looking back, one of the most valuable lessons I learned at Purdue was that economics is a way of thinking, a practical framework for understanding complex problems and helping people make informed decisions when the answers are uncertain and the stakes are high.
Technologies change. Markets evolve. Policy debates come and go. Yet the need for rigorous, evidence-based decision making remains constant.
Hiroaki Ishigaki holds an MS and PhD in economics from the Mitch Daniels School of Business. A pioneer in Japanese antitrust and competition-policy economics, he served as a merger-review economist at the Japan Fair Trade Commission before joining NERA in 2006, where he helped establish its antitrust economic consulting practice in Japan. As Head of NERA’s Tokyo Office, he advises law firms, corporations, and government agencies on mergers, cartels, intellectual property, securities, finance, transfer pricing, commercial disputes, and energy policy. He provides evidence-based analysis in regulatory investigations, litigation, strategic advisory work, commissioned METI and JFTC research, and cross-border matters worldwide.
