Trends in Social Distancing - Part 2

A few weeks ago, I wrote Part 1 of this series. It looked at anonymous smartphone data from several different sources. In all cases, I found that social distancing started after WHO declared a pandemic, even though the shutdowns did not begin until a week or two later. In this update, I now have data on Thanksgiving. Many feared that there would be a surge in cases after people celebrated the holiday together. But it looks like there was little change in social distancing. 

One of my sources, SafeGraph, changed its methodology, so I am not using it anymore. I still have data from the adjusted device exposure index (DEXA). Every day, it tracks how many smartphones were in each store (more information in Part 1). In the graph, time (t) is zero on January 20, when the first case in the US was confirmed. So Thanksgiving is around t = 300. There isn't a big spike during the holiday. But perhaps this is not the best data source to capture that. Gatherings happened in people's homes, not in stores. However, it should pick up a Black Friday surge. It is hard to spot it on the graph, so this means that people were shopping online instead.

DEXA

If social distancing fell during Thanksgiving, it should show up in the trips data (more information in Part 1). This is collected by the Department of Transportation. If you look closely, there does seem to be an increase around t = 300. However, it is pretty small.

Number of Trips

The Department of Transportation also estimates how many people left their homes. It was actually trending downwards before Thanksgiving. That isn't surprising; cases were rising, so people became more cautious. The trend briefly reversed for the holiday, but now it is heading back down. Once again, Thanksgiving only has a small effect.

Percent of people who left home

I don't have data on Christmas yet - when the Department of Transportation posts an update, there is a lag of about one or two weeks. Stay safe