Artificial Intelligence and Tax Behavior: A Field Experiment

We mailed postcards to a random sample of households that pay property taxes and could legally reduce their taxes by filing an appeal.

2026-05-01

2026-05-15

The main outcome of interest is whether the household filed a tax appeal on its own; the 2026 filing deadline is May 15. For households assigned to the chatbot treatment, a key secondary outcome is chatbot usage, including whether they interacted with it at all and, if so, what questions they asked.

Given the nature of the setting and the timing of the protest process, we expect the intervention to affect primarily whether households file a direct protest. For this reason, we will focus on direct protests as the primary outcome. We also plan to use direct protests in prior years as falsification, or placebo, outcomes in the spirit of an event-study analysis.

The rich administrative data will also allow us to examine additional outcomes. For example, we can estimate effects not only on whether households file an appeal, but also on whether their appeal is successful. We may also be able to obtain information on the Opinion of Value (for households who file an appeal), which could be potentially an outcome of interest. For households assigned to the chatbot treatment, we can also analyze chat transcripts to study the content and dynamics of their interactions.

Some households are randomly selected to receive a postcard with a URL directing them to a website. Screenshots of a sample postcard and a sample website are attached to this preregistration.

Not available

Randomization done in office by a computer

Household

No

61,474 households. However, as explained above in 'Experimental Design,' some of these households will need to be dropped ex post; for example, if they had already filed an appeal by the time our postcards were delivered.

61,474 households (again, some of these households will have to be excluded from the sample)

45,200 households are sent a postcard, while the remaining 16,274 households are not.

Among households that receive a postcard, we randomly assign them to one of two sub-treatments:
- 50% are assigned to a website without a chatbot.
- 50% are assigned to an otherwise identical website with a chatbot.

And among households assigned to the chatbot condition, we randomly assign them to one of two sub-treatments:
- 50% are assigned to a more human-like version ('Marina').
- 50% are assigned to a less human-like version ('Chatbot').