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This Equation Relates Single-Link to Complete-Link to Average-Link to … Others. Lance and Williams (1967), “A General Theory of Classificatory Sorting Strategies,” Computer Journal , 9, 373-380.
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This Equation Relates Single-Link to Complete-Link to Average-Link to … Others Lance and Williams (1967), “A General Theory of Classificatory Sorting Strategies,” Computer Journal, 9, 373-380. They created an equation that, if you change the weights, you could see a whole family of clustering algorithms and how they’re related: d = dissimilarity or distance between h = some object we're contemplating adding to the cluster dh,k = Aidh,i + Ajdh,j + B di,j + C |dh,i - dh,j | k = the current cluster with members: object i & j algorithm Ai AjB C single-link .5 .5 0 -.5 complete-link .5 .5 0 .5 avg-link 0 0 Alenderfer and Blashfield has a typo, p.38; says C = 1/2 for single). See Seber(pp.360-365) and Hartigan excerpt.