False Positives mean R can never reach zero and will remain around 1 indefinitely

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False Positives mean R can never reach zero and will remain around 1 indefinitely


If prevalence was low enough that most positives were false, cases would appear to stop falling & settle at a low level (+noise).

R would rise from below 1 to around 1 & jump around at that level.

Indefinitely.

E.g. below. % of positive tests declines; then settles at a low but non zero level. If R is determined by the changes in this number (slope of graph) it would be <1 during decline, then rise & settle around 1 but with significant variation due to noise etc being larger at low levels.





@RuminatorDan


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