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This the main chart from the deck justifying the new tiers. It's a nice neat distribution but the problem is that the objective should be more about balancing wider public/mental health and economic risks/costs - not drawing a pretty (i.e. evenly spread) chart. 1/
It feels to me like someone decided what tiers they wanted, along with the proportion of the country they wanted in each - and then fitted the distribution to it. A more balanced/targeted consideration of local factors perhaps wouldn't result in such a neat fit? 2/
Unsurprisingly, I've drawn my own! Plotted here again for 19-Dec to show it generally comes out the same. Points above the dotted line mean they've dropped in the recent week. Why haven't the new tiers taken into account the improving situation? 3/
Same chart, but plotted for the day we went into national lockdown. Many more areas below the line showing that they were still increasing at that point in time. 4/
I don't much like this quote from the deck. The author is advocating stronger restrictions into the new year despite the data already being better than when we went into national lockdown. That's a serious escalation of the proportionality of the response. 5/
Another issue is the change in granularity of the restrictions. If I plot the same chart for local authorities, the distinction is much less clear. Particularly bad for those tier 3 areas stuck down towards the lower end of the orange. 6/
E.g. we've got Tier 3 areas from Kent, Lancashire and Warwickshire all the way down here. All but 1 are above the line so are improving too. 7/
I don't know where these "sub-regions" have come from as I've not been able to find an official reference and had to reverse engineer them from the document. They are much larger areas than local authorities. Can only a whole sub-region be moved back out of a given tier? 8/
They've not used the very latest data by announcing the tiers so soon and only looking to 19-Dec. It'll be over 2 weeks old by the time it comes into effect. Here's the chart for just 2 days later and already all but 2 points are above the dotted line. 9/
Overall I'm unimpressed with this latest attempt. The old tier system certainly had its own problems, but the intervening national lockdown has caused all the local consideration and measured escalation to be thrown away and now we're starting again from scratch. 10/
Waiting until 16-Dec to review this downward trending situation is too long. I already think some of the areas have been placed in too high a tier and we're still a week away. The tiers need to be reconsidered before next Thursday and the 1st review date needs to be sooner. END.
