This is false, the R value cannot tell you about the future or wether graphs are ‘likely to go down’. They tell you wether the graph is going down, which you can tell from the graph. It just quantifies this.

This is exactly why the R value is not very useful. It is calculated over historical data so it has no predictive power whatsoever. However, it does falsely appear to have this power. Quote:

> There is always a slight time lag in the R number of a matter of weeks

> There is always a slight time lag in the R number of a matter of weeks

ah ok: that's not what I understand from how governments are reporting it.

My understanding is that it's the (best estimate) of how virus cases are spreading today.

Since the graph of cases for today tells you how the virus has spread in the last two weeks, that's not the same information.

If you claim that R is only estimated from the historical number of cases, then R is not giving you information that you couldn't technically identify from this graph, I agree. However, R could be estimated using other information.

I’m no statistician, but for me the most egregious failures on this have been constant use of ‘The’ R number and ‘The’ curve. The implication is that we have a single infallible measure that’s universally applicable, with no reference to exactly how R from different studies were weighted to come up with the announced figure, or how the sample populations of each study were skewed.