EstimationWindows

Computes estimation windows from assignment groups.

The window for a group spanning observations from startIndex to endIndex reaches floor(delta * m) observations into each neighbour, where m is the group's own size, clipped at the ends of the sample. At delta of zero the window is the group.

The window is defined from the group's own size, not its neighbours', and that is not a detail. The exact segmentation dynamic program requires the cost of a segment to depend on its own two boundaries and nothing else. A window defined as a fraction of the neighbours' sizes would depend on the boundaries either side of those, the recursion would no longer be a chain, and the linear-time result would be lost. A fraction of the group's own size keeps the dependence local.