4-3.1 Bimodal distribution of comparison weights.

Refer now to figure 2 below. This figure is actually an idealized version of a frequency polygon based on the histogram constructed by charting weights for all the comparisons made in blocks. The negative weights, which represent fractional powers of two, tend to be those for unmatched comparisons. The positive represent in large part the matched comparisons. Thus the curve is bimodal.

In this case we do not have a model for the frequency density distribution. This means that we can only guess at the two curves underlying the two modes. A conservative estimate is outlined on the figure with the dotted lines. The green line is a pretty much minimal estimate of the intrusion of the unmatched on the matched, and the orange, the matched on the unmatched. Aiding this guess is an important observation: the proportion of linked to unlinked at zero should be about the same as the proportion of the two totals.

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