Professor Ali Makhdoumi reveals why your friend's social media activity might be compromising your privacy, even when you share nothing at all

Every time your colleague shares their location data or a friend posts their workout routine, they're inadvertently exposing details about you–even if you've never agreed to share your data. This hidden web of data spillovers means companies can predict your preferences, behaviors, and personal information simply by analyzing the digital footprints of people in your network.

In this episode, Professor Ali Makhdoumi of Duke University's Fuqua School of Business discusses his research on personal data markets, based on his paper "Too Much Data: Prices and Inefficiencies in Data Markets," co-authored with 2024 Nobel Prize winner Daron Acemoglu. He explains that what we think of as personal, private data is actually more like a public good. Platforms can infer your information indirectly through your connections, creating what economists call "data externalities."

Makhdoumi explores why current data markets are so structurally inefficient. When your data can be predicted from others' sharing decisions, you lose bargaining power and companies acquire personal information at depressed prices. This creates market dynamics where users share more data than is socially optimal, often receiving compensation that doesn't reflect the full social costs.

The implications extend beyond individual privacy concerns. Makhdoumi's research shows that under certain conditions, shutting down data markets entirely would improve societal welfare. For business leaders, this challenges conventional thinking about data as a valuable corporate asset and raises questions about sustainable data strategies.

Makhdoumi proposes innovative solutions, including "decorrelation" techniques that could allow beneficial data sharing while protecting privacy. He also outlines policy approaches that could help realign market incentives with social benefits. The research offers a framework for companies thinking more strategically about data acquisition, user trust, and the long-term sustainability of data-driven business models.

Duke Fuqua Insights features digestible conversations with our faculty about the most impactful research from their careers, including studies they teach in Fuqua classes. New episodes every other week in season.

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