O-Cluster Options
The default settings are designed so that they should work
for most cases.
You can change the following settings:
- Maximum Number of Clusters: A positive integer that specifies the maximum number of clusters; default is 10. O-Cluster finds "natural" clusters by identifying areas of density within the data, up to the maximum number entered as a parameter. That is, the algorithm is not forced into defining a user-specified number of clusters, so the cluster membership is more clearly defined.
- Sensitivity: Must be between 0 (fewer clusters) and 1 (more clusters); the default is .5. This setting determines how sensitive the algorithm is to differences in the characteristics of the population. O-cluster determines areas of density by looking for a "valley" separating two "hills" of density in the distribution curve of an attribute. A lower sensitivity requires a deeper valley; a higher sensitivity allows a shallow valley to define differences in density. Thus, a higher sensitivity value usually leads to a higher number of clusters. A higher number of clusters can result in a longer build time.
- Maximum Buffer Size: The maximum size of the memory buffer, in logical records, that can be used by the algorithm. The default is 50000 logical records. For more information about maximum buffer size, see Maximum Buffer Size for O-Cluster Models.
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