While researching a topic, a student has taken the following notes:

A 2022 study analyzed geotagged social media posts to assess the effect of parks on happiness in 25 US cities.
The happiness benefit of a city's parks was the numeric difference between the calculated happiness scores of posts made in parks and posts made elsewhere.
A benefit above 0 indicates a positive effect.
The park happiness benefit in San Francisco, California, was greater than 0.10.
The park happiness benefit in Washington, DC, was greater than Obut less than 0.10.
The average happiness benefit of parks across all cities was 0.10.