Back to the future

Way back in the mists of time (ie, 2006), jules and I saw what was going on with people estimating climate sensitivity, and in particular how this literature was interpreted by the authors of the IPCC AR4. And we didn’t like it. We thought that any reasonable synthesis should consider the multiple lines of evidence…

Like a phoenix redux

Even odder than finding that our old EnKF approach for parameter estimation was particularly well suited to the epidemiological problem, was finding that someone else had independently invented the same approach more recently…and had started using it for COVID-19 too! In particular, this blogpost and the related paper, leads me to this 2013 paper wherein…

Like a phoenix…

So, the fortnightly chunks in the last post were doing ok, but it’s still a bit clunky. I quickly found that the MCMC method I was using couldn’t really cope with shorter intervals (meaning more R values to estimate). So, after a bit of humming and hawing, I dusted off the iterative Ensemble Kalman Filter…

More COVID-19 parameter estimation

The 2 and now 3-segment piecewise constant approach seems to have worked fairly well but is a bit limited. I’m not really convinced that keeping R fixed for such long period and then allowing a sudden jump is really entirely justifiable, especially now we are talking about a more subtle and piecemeal relaxing of controls.…

The EGU review

Well.. that was a very different EGU! We were supposed to be in Vienna, but that was all cancelled a while back of course. I might have felt sorry for my AirBnB host but despite Austria banning everything they didn’t reply to my communication and refused a refund so when AirBnB eventually (after a lot…

Why can’t the Germans be more like us?

And now for the previous post, in reverse. Germany locked down at about the same time as the UK. Actually probably a couple of days earlier, according to Wikipedia and Flaxman et al. Picking a single date is a bit subjective really, but for the purposes of this post I’ll choose the 21st March. So…

The human cost of delaying lockdown

A while ago, I mentioned that the cost of delaying lockdown by a week was to increase illness and death by a factor of 5, based on the doubling time of 3 days that the virus seemed to have at the start. Human cost of delayed action – a short thread prompted by a tweet…