Current Data Methodology
The visitdata.org website is powered by Foursquare’s US foot traffic data, derived from our panel of 13 million always-on opted-in users. Visits by that panel are normalized 1) for changes in the panel's size, and 2) to better reflect the age-gender distribution of each state. Note that the panel data, and the normalized estimated number of visits derived from the panel data, are subject to various errors and biases.
To learn more about Pilgrim – Foursquare’s “snap-to-place” technology which powers our visit data – click here.
Prior Data Methodology
Prior to May 1, 2020, the methodology was as follows:
The data is represented as an index. Foot traffic for a given county on a given day is indexed to average foot traffic for that county in the month of February 2020. Increases or decreases relative to that average are corroborated with a measure of statistical significance. In this case, we are simply testing for a difference in means, given “n” size, effect size, and variance.