Taking one step back, this applies to coronavirus and data in general. We don't have accurate data on case numbers, because testing capacity has varied with ti

Taking one step back, this applies to coronavirus and data in general. We don't have accurate data on case numbers, because testing capacity has varied with time and between countries, and the precise specificity and sensitivity of the PCR and serology tests, in the real world, are not known. There are biases is reporting of the illness, deaths, those tested. Never before have we had so much data to deal with such a challenge to our society, and yet, the data we do have is not representative of the natural process, and often doesn't help us to understand a model of what is going on. Getting data on mobile phone adjacency is just adding to the large amount of poor quality data.