Ward’s algorithm can produce sub-optimal solutions - cases cannot be reallocated to more suitable clusters at a later stage in the algorithm.

• Ward’s algorithm can produce sub-optimal solutions - cases cannot be reallocated to more suitable clusters at a later stage in the algorithm.

• K-means algorithm can reallocate cases.

• BUT…

• Implementation of k-means in some software packages can produce different results from the same data through starting with different cluster centroids…