subcategories. Subcategories are ordered from most early adopter-leaning to
most holdout-leaning, according to Figure 4c. Shaded regions represent
bootstrapped 95% CIs.

1

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1

#### Acknowledgements.

The authors thank Ruth Appel, Jonas Barklund, Lisa Cooper, Victor Dibia, Rahul
Dodhia, Irena Gao, Kristina Gligorić, Ece Kamar, Paul Koch, Jure Leskovec,
Besmira Nushi, Mayana Pereira, Emma Pierson, Yusuf Roohani, Rok Sosic, Albert
Sun, Johan Ugander, Michihiro Yasunaga, and members of Johan Ugander’s lab for
helpful discussions and support. S.C. conducted this work as an intern at
Microsoft.

#### Author Contributions.

S.C. performed computational analysis. All authors jointly analyzed the
results and wrote the paper.

#### Author Information.

The authors declare no conflict of interest. Correspondence should be
addressed to<EMAIL_ADDRESS>
#### Data Availability.

Our vaccine intent estimates and ontology of vaccine concerns are publicly
available at https://github.com/microsoft/vaccine_search_study. Aside from
Bing search logs, all of the data sources that we use are publicly available
online. The CDC data, US Census data, and Google search trends can be directly
downloaded, and the elections data and Newsguard data can be purchased at the
references provided in Section M1.

#### Code Availability.

Our code for running experiments and generating figures is also publicly
available at https://github.com/microsoft/vaccine_search_study.