Professor Tadelis is an expert on e-commerce and the economics of the internet, industrial organization, and microeconomics, including game theory and auction theory. His work on e-commerce investigates online auctions and online bargaining, digital advertising, seller reputation and the determinants of trust, price salience, and algorithmic pricing. Professor Tadelis has also researched contract theory and design, with applications to outsourcing, privatization, strategic pricing, public and private sector procurement and award mechanisms, and strategic sourcing and pricing. He has been engaged by regulatory authorities and tech companies in a variety of investigations and litigation matters in both the US and Canada on topics such as consumer protection, pricing, and online advertising and has testified at deposition. Professor Tadelis has a decade of experience working with online marketplaces and retailers. He served as a senior director and distinguished economist at eBay Research Labs, where he hired and led a team of economists focused on the economics of e-commerce, with particular attention to creating better matches of buyers and sellers; reducing market frictions by increasing trust and safety in eBay’s marketplace; understanding the underlying value of different advertising and marketing strategies; and exploring the market benefits of different pricing structures. He also served as vice president of economics and market design at Amazon, where he guided and supported economic analyses for business decisions across the company.