COVID-19 Forecast: China as a Reference

COVID-19 Forecast: China as a Reference

With the onset of the COVID-19 outbreak, we look at the data and use a simple model inspired by China’s example to predict when the outbreak will abate in various countries.

You can learn about the method we used to calculate these numbers, or skip directly to the forecasts (updated daily).

The forecasts tell us that we, every human being, needs to keep following the measures (social distancing, diligent heygenic habits, etc.) for around 70 days for the pandemic to abate.

Let’s stick together (metaphorically, see social distancing) and stop the pandemic! Stay safe everyone!

Disclaimer: While every care has been taken to make the forecasts as accurate as possible, the forecasts are provided “as is”, without warranty of any kind, express or implied.

Forecasts

Note: the graphs show the total number of cases since the start of the outbreak, not the number of cases per day.

Method

Since China was the first country hit, they took strong measures in response to the pandemic. Although the response was criticized in the beginning, most countries now followed suit. China therefore serves as a plausible reference to how the outbreak develops in various countries.

Examining the data, the number of new cases in China looked very similar to the known sigmoid function. We follow an (admittedly simple) model: we fit a parameterized sigmoid function over the data from each country to estimate:

  • response date: the date when the country effectively started responding to the outbreak
  • recession date: the date after which the number of daily new cases is 5 or less
  • error: the maximum estimation error (as a percentage) over the past 10 days.

Note: we created our own metrics here, please enlighten us if you have sounder ones.

Examining the response dates of China, South Korea and Germany, they are estimated by error of no more than 3 days.

Remarks

In the forecasts section we show countries where there was a reasonably good fit. Other countries either have too little data or they potentially follow a different curve.

We keep updating the forecasts as more data comes (mostly daily).