Closing one debate on reopening

On the most recent episode of Vox's "The Weeds" podcast, titled "Who models the modelers?", Ezra Klein and Matt Yglesias discuss the overwhelming sense of uncertainty that permeates all discussion about the coronavirus: how long our lockdowns should last, whether it's OK to venture outdoors into parks or not, and how best to reopen our economies.

Eventually they alight on the U.S. state of Georgia, whose governor (Brian Kemp) recently announced the gradual "reopening" of his state. (Side note: depending on whom you believe, Kemp did this with the express consent and agreement of both the president and vice-president. After Kemp announced the policy change, however, Trump executed an immediate about-face and told the press he "disagree[d] strongly" with Kemp's decision. Turns out loyalty isn't quite as contagious as COVID-19.)

After debating the merits of Kemp's decision, Klein pivots to a tangential discussion about what reopening Georgia would even mean:

One thing I don't think we know...is how much social distancing and closure do you need to get most of the effect? And Brian Kemp saying that he's going to open up nail salons and bowling alleys...[but] a lot of people aren't going to go...

...And so one thing that may happen here is Kemp reopens Georgia, [but] Georgia does not really reopen...and so it basically moves the needle like 20% towards reopening, but that actually isn't enough to create a catastrophe...

...I think there's also going to be this potential for an outcome where Kemp has officially reopened Georgia, but people in Georgia haven't followed the reopening path. And so it looks like he was right to reopen, but what actually happened is social distancing continued. It's going to be very hard to track and understand some of these things correctly.

Yglesias agrees, saying: "You shouldn't overrate the public official's ability to drive human behavior." The two conclude that there is essentially no way to evaluate the efficacy of a state's reopening given the distinct possibility that its fearful residents may continue social distancing anyway -- and paradoxically, this very policy failure to induce societal behavioral changes may end up contributing to its perceived political success.

These are interesting observations as far as they go. But it is, perhaps, inevitable in an episode that included phrases like "I'm not an epidemiologist, but..." that Klein and Yglesias neglected multiple public data sources from prominent technology companies that could help us decipher just how effective a state's or country's reopening can be.

Google, Apple, Facebook, and now even The Guardian (using TomTom data) have all published detailed city- or county-level "mobility" data comparing current human movement patterns to a pre-pandemic baseline. Their methodologies and primary data sources vary, which is a short way of saying that collectively they represent a plethora of new information about real-life human responses to the threat of COVID-19.

Google's most recent report on Fulton County in Georgia (the home of Atlanta), for example, shows a stark decrease in traveling activities for everything from retail to parks to transit stations to the workplace:

Apple's data for Atlanta (shown in this newsletter's headline image) is even more up-to-date, featuring figures through yesterday, and shows daily walking, driving, and transit directions requests on Apple Maps plummeting between 41% and 64% since January 13th. Facebook calculates a "relative mobility change" (-21%) as well as a "stay-put percentage" (18%), both of which show Georgians demonstrably tamping down their movement. The Guardian's traffic dataset, meanwhile, compares Atlanta traffic in February and early March, when road congestion routinely increased travel times by 60% or more against a traffic-free baseline, to the city's traffic in April, where that figure has yet to break 20%.

Of course, given its recency, the effect of Governor Kemp's announcement on actual Georgians' behavior remains to be seen. But -- and this is the point -- it will be seen.

Indeed, it may one day make for a particularly interesting retrospective, quantitative study on which of these "laboratories of democracy," better known as U.S. states, most successfully navigate the public health crisis. One can imagine all sorts of analyses: for example, the net mobility change of a given state's residents immediately following a gubernatorial "reopening" announcement could be measured as a proxy for the governor's political credibility with his constituents. But most crucially, a state's ability to successfully avoid a prolonged health crisis can be traced back to the actual empirical evidence of its residents' social distancing practices, rather than the whims of its politically-motivated leaders.