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Obtaining Raw Sample Points.

In the case of measures which are already statistics of the whole population at any given time (i.e. Cumulative Activity, Mean Cumulative Activity, and Diversity), these 10 sample points could be taken directly from the value of the measure at the appropriate time. However, to prevent high-frequency changes in these measures from producing aberrant results, the measures were smoothed before the samples were taken (using median-smoothing with a window of 10,000 time slices).

In the case of the measures where the existing data consisted of multiple values at each time slice, each representing individual programs (i.e. the Program Length and Replication Period measures), each of the 10 sample points was produced by taking the median value of all values lying within a window of 1000 time slices around the time slice being sampled.

Tim Taylor