What does "Weighted Pairs" mean?

Question

In statistical analysis, what does "weighted pairs" mean?

An example I'm looking at reads "Butter has a purchase cycle (weighted pairs) of 60.2 days".

Thanks in advance.

Answer 1

*Weighted pair-group average.* This method is identical to the unweighted pair-group average method, except that in the computations, the size of the respective clusters (i.e., the number of objects contained in them) is used as a weight. Thus, this method should be used when the cluster sizes are suspected to be greatly uneven.

*Unweighted pair-group average.* In this method, the distance between two clusters is calculated as the average distance between all pairs of objects in the two different clusters. This method is also very efficient when the objects form natural distinct "clumps," however, it performs equally well with elongated, "chain" type clusters.