The Development of Circadian Rhythms in Human Infants

proportion of the total variance of the observed data that is „explained‟ by the fitting
pattern. For the 93 infant weeks that were sampled the mean amplitude was 0.0288
with maximum and minimum values 0.0035 and 0.1092 respectively.
The resultant graphs for infants 16003 and 16004 are shown for direct comparison
(Fig 8.3.). Data on all infants is included in appendix 4. Graphs were drawn using R
statistical package (R version 2.7.2 2008 The R Foundation for Statistical
Computing).
For clarity a description of the symbols used in the gene plots and a key are given
below:
Separate graphs have been prepared for each observed week of each infant showing
the level of expression plotted against time, with two curves superimposed: i) the
fitted sinusoidal curve for that week‟s data, as an unbroken line and ii) the fitted
sinusoidal curve from the week (for the same infant) that has the best fit,
corresponding to the greatest amplitude of the pattern, as a broken line. In other
words, the week with greatest amplitude of gene expression was superimposed
(represented by broken line) onto each week of individual measurement (represented
by unbroken line) for ease of comparison. For each infant, therefore, the plot for that
week with the best fit does not have a second curve superimposed. Each of these
graphs is annotated with the amplitude, hour of maximum fitted level, the R-squared
statistic, and the P-value from that individual linear regression
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