about

I am an incoming post-doctoral researcher in Economics at Stanford University, where I will work with Arun Chandrasekhar. Beginning in September 2026, I will join Oregon State University as an Assistant Professor in Statistics.

I completed my PhD in Statistics at the University of Wisconsin-Madison, where I was co-advised by Keith Levin and Karl Rohe. I study spectral methods for network analysis, causal inference, and causal inference on networks. You might know me from my work on broom, a popular open-source R package in the tidyverse.

My curriculum vitae is available here. I also keep Google Scholar up to date. You can find me on Bluesky at @alexpghayes.com.

Headshot of Alex

what i’m doing now

As of August 2025, I’m putting my time towards:

  • Packing up and moving to Palo Alto
  • Finishing up a project on asymptotic collinearity of peer effects in the linear-in-means model
  • Figuring out how to estimate peer effects in noisy networks
  • Developing guardrails to detect when hard-to-measure metrics regress in huge online experiments
  • Making data collection for in person social networks cheaper and more efficient
  • Software development to keep R packages up to date and on CRAN

From August 3 to August 7, 2025 I will be at the Joint Statistical Meetings 2025 in Nashville, Tennessee. I’m presenting on Thursday in the Business and Economic Statistics Student Paper Awards session:

Peer effects in the linear-in-means model may be inestimable even when identified
Thursday, Aug 7: 8:30 AM - 10:20 AM
Music City Center, Room CC-103C

pre-prints

  1. Peer effects in the linear-in-means model may be inestimable even when identified. Alex Hayes and Keith Levin. arXiv. October 14, 2024.

publications

  1. Estimating network-mediated causal effects via principal components network regression. Alex Hayes, Mark M. Fredrickson, and Keith Levin. Journal of Machine Learning Research. 2025. replication package, code

  2. Co-factor analysis of citation networks. Alex Hayes and Karl Rohe. Journal of Computational and Graphical Statistics. 2024. post-print, arXiv, replication package, code

  3. Welcome to the tidyverse. Hadley Wickham, Mara Averick, Jennifer Bryan, Winston Chang, Lucy D’Agostino McGowan, Romain François, Garrett Grolemund, Alex Hayes, Lionel Henry, Jim Hester, Max Kuhn, Thomas Lin Pedersen, Evan Miller, Kirill Müller, David Robinson, Dana Paige Seidel, Vitalie Spinu, Kohske Takahashi, Davis Vaughan, Claus Wilke, Kara Woo, Hiroaki Yutani. Journal of Open Source Software. 2019. website

blog

In a hobbyist capacity, I also blog about statistics, programming, and data. Some posts I’m particularly proud of: