Period and confidence intervals for strongly dampened data.

Data sets of strongly dampened data were analysed using SR and NLLS; the mean period and the mean confidence intervals are reported in the table (standard deviations are in brackets). The data sets were created by linear dampening the standard test data (5 days duration, hourly sampled, 24 h underlying period) in such a way that the signal reached 0 at the selected day, then uniform noise was added at 40% of the original amplitude. The results were classified to be accurate (acc) or false positives (false) depending on their period value: accurate periods were 24±0.5 h, while false positives were periods in the range (18–30 h) that were not accurate. 1) Shape of the base signal before dampening: pulse (pul) and double pulse (dblp). 2) The reported values are mean period (MP), and mean confidence intervals for accurate results (CI (acc)) and false positives (CI (false)). 3) Dampening level, represented as the day at which the initial rhythmic signal was reduced to 0, for example Dmp. 4 means that at the end of the 4th day the signal was 0 and followed by a flat line (before adding the noise).