Sequence plots of time-series of observations of weekly-averaged proportions of A) upper and B) lower respiratory tract infections to total house visits in the area of Athens, Greece as recorded by SOS Doctors from January 01, 2000 to October 12, 2008.
Superimposed are the results of the reference standard classification procedure. The green continuous line represents estimated baseline level. Green broken line over baseline represents threshold. The observations identified as unexpected have been plotted in red color.