About

Guy Aridor is an assistant professor of marketing at the Kellogg School of Management at Northwestern University. He holds a PhD in Economics from Columbia University. His research focuses on questions regarding consumer privacy, recommendation systems, and social media, with a particular interest in policy and antitrust issues in these spaces. His work has been published or is forthcoming in several venues across economics, marketing, and computer science, including the RAND Journal of Economics, Management Science, the Journal of Economic Literature, and the Proceedings of the ACM Conference on Recommender Systems. Prior to his PhD, he worked as a software engineer at HubSpot, where he focused on growth engineering and developing marketing automation tools.

Research topics

• Computer Science
• Business
• Computer Security
• Internet privacy
• Economics
• Human–computer interaction
• Microeconomics
• International trade
• Advertising
• World Wide Web
• Industrial organization

Selected publications

• Digital News Consumption: Evidence from Smartphone Content in the 2024 US Elections

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access1st authorCorresponding
  PublisherDOI

• Measuring Substitution Patterns in the Attention Economy: An Experimental Approach

  The RAND Journal of Economics · 2025-07-21 · 7 citations

  articleOpen access1st authorCorresponding

  ABSTRACT Substitution patterns are a crucial input to antitrust analysis, but measuring them for free digital products has proved difficult due to the lack of price variation. I measure substitution patterns by installing software on experimental participants' Android phones that restricts access to Instagram or YouTube—generating variation in choice sets—and monitoring how participants reallocate their time. I find that participants substitute to multiple product categories in both restrictions but also substantially for nondigital activities. These results imply that using product characteristics as a proxy for relevant markets may incorrectly specify the relevant set of substitutes in these contexts.

  PublisherOA PDFDOI

• Does Transparency Matter in Opaque Product Markets? Insights from Privacy

  AEA Randomized Controlled Trials · 2025-06-02

  dataset1st authorCorresponding
  PublisherDOI

• Evaluating the Impact of Privacy Regulation on E-Commerce Firms: Evidence from Apple’s App Tracking Transparency

  Management Science · 2025-11-20 · 4 citations

  article1st authorCorresponding

  Assembling novel data sets on online advertiser spending, performance, and revenue, we quantify the economic effects of Apple’s App Tracking Transparency (ATT) privacy policy on e-commerce firms. We find that conversion-optimized Meta advertisements, affected most by ATT, saw a 37% reduction in click-through rates after ATT. Although firms responded by shifting ad spending from Meta to the Google ecosystem, firms with higher baseline Meta dependence nevertheless experienced a substantial decline in firm-wide revenue relative to firms with lower baseline Meta dependence. We quantify these effects using a variety of methods, finding revenue decreases in the range between 8% and 40% relative to less exposed firms. These declines were primarily borne by smaller e-commerce firms, raising questions about the tradeoffs between consumer privacy and the ability of smaller e-commerce and direct-to-consumer firms to succeed in the product market. This paper was accepted by Jean-Pierre Dube, marketing. Funding: This work was supported by the LEC Program on Economics & Privacy, MSI Research Grant [4001820]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2024.06600 .

  PublisherDOI

• Competing Bandits: The Perils of Exploration Under Competition

  ACM Transactions on Economics and Computation · 2025-01-10 · 5 citations

  article1st authorCorresponding

  Most online platforms learn from interactions with users and engage in exploration : making potentially suboptimal choices to acquire new information. We study the interplay between exploration and competition : how such platforms balance the exploration for learning and competition for users. We consider a stylized duopoly in which two firms face the same multi-armed bandit problem. Users arrive one by one and choose between the two firms, so that each firm makes progress on its bandit problem only if it is chosen. We study whether competition incentivizes the adoption of better algorithms. We find that stark competition disincentivizes exploration, leading to low welfare. However, weaker competition incentivizes better exploration algorithms and increases welfare. We investigate two channels for weakening the competition: stochastic user choice models and a first-mover advantage. Our findings speak to the competition–innovation relationship and the first-mover advantage in the digital economy.

  PublisherDOI

• Does Transparency Matter in Opaque Product Markets? Insights from Privacy

  AEA Randomized Controlled Trials · 2025-06-02

  dataset1st authorCorresponding
  PublisherDOI

• Information-constrained coordination of economic behavior

  Journal of Economic Dynamics and Control · 2024-11-07 · 2 citations

  article1st authorCorresponding
  PublisherDOI

• Evaluating the Impact of Privacy Regulation on E-Commerce Firms: Evidence from Apple's App Tracking Transparency *

  SSRN Electronic Journal · 2024-01-01 · 1 citations

  articleOpen access1st authorCorresponding
  PublisherDOI

• The Economics of Social Media

  SSRN Electronic Journal · 2024-01-01

  articleOpen access1st authorCorresponding
  PublisherDOI

• Experiments on Social Media

  SSRN Electronic Journal · 2024-01-01 · 4 citations

  articleOpen access1st authorCorresponding
  PublisherDOI

Frequent coauthors

• Duarte Gonçalves

  University College London

  9 shared

• Aleksandrs Slivkins

  7 shared

• Daniel Kluver

  Twin Cities Orthopedics

  7 shared

• Joseph A. Konstan

  University of Minnesota

  7 shared

• Yeon‐Koo Che

  Columbia University

  7 shared

• Roee Levy

  Tel Aviv University

  6 shared

• Duarte V. Gonçãlves

  Universidade do Porto

  6 shared

• Zhiwei Steven Wu

  5 shared

Awards & honors

• Best paper at 2026 Econometric Society 2026 CSW Asia Meeting
• Econometric Society Best Short Paper at ACM Conference on Re…