Alan Warren wrote to observe that the >=30 starting threshold visualizes some weird artifacts having to do with Diamond Princess accounting. Basically, more than 30 passengers were flown to the US in mid-Feb, and JHU starts counting these as US cases on 2/23 (arbitrarily), which means that's the date we start counting the US as passing the threshold.
I do think these US cases should be included and plotted, but I agree that that part of the plot shows the effects of a different policy regime where every case was being well-separated and scrutinized, unlike today.
Maybe it would be clearer to have default starting threshold should be >=80, which skips past the time period with these differences. All the countries and states have a day where they have (logarithmically) a bit more than 80 known cases, so it's a good tightly-clustered threshold.
Alan Warren wrote to observe that the >=30 starting threshold visualizes some weird artifacts having to do with Diamond Princess accounting. Basically, more than 30 passengers were flown to the US in mid-Feb, and JHU starts counting these as US cases on 2/23 (arbitrarily), which means that's the date we start counting the US as passing the threshold.
I do think these US cases should be included and plotted, but I agree that that part of the plot shows the effects of a different policy regime where every case was being well-separated and scrutinized, unlike today.
Maybe it would be clearer to have default starting threshold should be >=80, which skips past the time period with these differences. All the countries and states have a day where they have (logarithmically) a bit more than 80 known cases, so it's a good tightly-clustered threshold.