Clear messages are good. Nonsensical equations are not.

Last week, we wrote a piece about how difficult it is at the moment for government to strike the right balance between delivering clear, easy-to-digest messages, and making sure that they are not oversimplifying things so far as to render the messaging unhelpful, confusing, and counter-productive.

Unfortunately, we don’t seem to be moving very fast towards that balance being struck.

On Sunday evening, Boris Johnson gave an address to the nation that has been pretty heavily criticised. We felt like some of the criticism was unfair (not to say a little boring and predictable, tbh): we cannot expect to hear messages of clarity when we are in the middle of a global pandemic caused by a virus that nobody fully understands yet. Of course there are going to be lots of “ifs”; for Johnson to speak with any level of certainty about the future would have been dishonest.

But while we thought the speech itself was OK, clearly it contained some major issues that have unfortunately led to yet more confusion. Foreign secretary Dominic Raab contradicted much of what Johnson had said on the Today programme on Monday morning, and seemed to not fully understand the new rules himself. Yes, these are tricky times, but we kind of feel like the government has had long enough to work out exactly what the new rules are, and to be able to express them clearly. (Perhaps the Zoom cabinet meetings are suffering from the same connectivity issues we regularly experience?)

We do think, though, that the new alert level system Johnson announced (something that South Africa instituted almost three weeks ago, as former Alphavillain Joseph Cotterill has pointed out) is a helpful one. Yes, it’s a bit crude, and the fact that we are being told we are between two categories (3 and 4) at the moment makes us feel like there should have been more categories. But at least it gives people an easy way to think about where we are, and a sense of progress.

But we think it would have been best if the government had left it at that. Surely the five-colour alert system is understandable enough? It literally has an equivalent on the Nando’s menu (as illustrated by Bryce “I don’t tweet work-related stuff” Elder on Twitter).

Instead, we were shown this as Johnson spoke:

This feels to us a bit like the mathematical equivalent of a mixed metaphor. (And perhaps, also, the equation equivalent of a chart crime.)

Using an equation to illustrate a point in a straightforward, clear fashion is fine, and can indeed be helpful. For example, the government could have done something like “Keeping the virus under control = social distancing + case isolation + hand-washing” (or whatever; we’re not paid to do this OK). This would be fine because although it’s not strictly an addition, we can see that we need all the parts of the sum to achieve “keeping the virus under control”. It’s also fine because no part of this equation is a number.

In the government’s example, all three parts of the equation must be expressed as numbers, and if you add them up, you actually get about 219,183.7 (because R is apparently currently between 0.5 and 0.9, and there have been 219,183 confirmed cases in the UK so far), not the 3.5(ish) alert level we are currently at. Some people are arguing it’s fine because it’s “symbolic” and shouldn’t be interpreted literally and that equations are often used in non-strictly-mathematical ways. But the problem is that these are mathematical figures, and the maths don’t add up.

We’re not trying to suggest that people are actually going to interpret the equation as meaning that the number of infections must actually be 2.8 or anything like that (ie 3.5 = 0.7 + 2.8). We don’t think they will. But the equation is yet another example of an attempt to oversimplify the messaging so far as to render it useless and confusing.

Because the other confusing thing about the equation is the fact that we need R as well as the “number of infections”. The way that scientists work out what R is precisely by looking at the number of new infections (while also taking into account the proportion of the population that remains susceptible to the disease). There’s not some thermometer-like gauge that spits out a number without needing any data inputs. Why do we need the “number of infections” bit at all?

Another of the government’s slides, shown below in part of a Twitter thread by the prime minister, seems to slightly contradict the one above, suggesting in fact that the alert system is in fact just about where R is:

We think the inclusion of the “number of infections” is probably there to give the government some leeway, so that they are not tied down to any policy when R reaches some given number (they have so far declined to specify what level it would have to reach in order for restrictions to be loosened). It also probably gives them some leeway in explaining the timing of the initial lockdown.

And there’s one further issue (and yes we might be being a touch pedantic here): the R keeps on being referred to as the “infection rate” but it’s actually not a rate. It’s a number. The reason it’s called “R” is not to signify “rate” but to signify “reproduction”: the reproduction number. (Again, you might have thought that people whose job it is to produce messaging would make sure they did an OK job of that.)

They say one shouldn’t shoot the messenger. But what about when it’s the messenger himself who is to blame?

Related links:
Is it acceptable for government to be dishonest at a time like this? - FT Alphaville
Axes of Evil - FT Alphaville

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