Create clusters – UVP Life Science User Manual
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LS Software User Guide
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Similarity and distance between lanes
Based on band matching, the similarity between two lanes L1 and L2 can be evaluated. Notations:
•
B1 is the number of bands in lane L1
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B2 is the number of bands in lane L2
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M is the number of matching bands in each lane, therefore
The similarity between two lanes can be measured using Dice or Jaccard scores. Dice similarity
formula is:
Jaccard similarity formula is:
The opposite to the concept of similarity is the concept of distance:
Distance values will be used to create the dendrogram.
Create Clusters
Initially, each lane has its own cluster. Then, repeatedly, a linkage rule (see below) is used to merge
smaller groups into larger clusters, until all the clusters have been combined into a single cluster. The
result is a hierarchy of clusters. Moving up the hierarchy contains clusters with more but less similar
lanes. Lanes that are very similar to each other will appear together in clusters near the bottom of
hierarchy.
The dendrogram shows the links that have been made between the clusters to form larger clusters
&endash; the shorter the distance between items in the dendrogram, the more similar they are.
Related Topics:
•
Linkage Rules