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Published on: February 15, 2017
Extended Quality (eQual): Radial Threshold Clustering Based on n-ary Similarity
Lexin Chen1,2, Micah Smith3, Daniel R Roe4
1Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States.
We optimized Radial Threshold Clustering (RTC) into Extended Quality Clustering (eQual), an O(N) algorithm. This new method offers faster, more consistent frame clustering, improving efficiency for large datasets.
Area of Science:
- Computational science
- Data science
- Algorithm development
Background:
- Radial Threshold Clustering (RTC) is an O(N^2) partitioning algorithm for grouping similar frames.
- RTC suffers from inefficiency with large datasets and order-dependent results during ties.
- Existing clustering methods may lack scalability and consistency.
Purpose of the Study:
- To transform the O(N^2) Radial Threshold Clustering (RTC) algorithm into an efficient O(N) algorithm named Extended Quality Clustering (eQual).
- To enhance clustering by improving speed and ensuring order-invariant results.
- To produce more compact and distinct clusters.
Main Methods:
- Implemented k-means++ for faster seed selection in frame clustering.
- Introduced extended similarity indices to select the densest and most compact cluster, ensuring order invariance.
- Developed Extended Quality Clustering (eQual) with a linear time complexity.
Main Results:
- Achieved O(N) time complexity, significantly improving efficiency over RTC's O(N^2).
- Ensured clustering results are invariant to the order of input frames.
- Demonstrated the generation of more compact and well-separated clusters.
Conclusions:
- Extended Quality Clustering (eQual) provides a scalable and consistent alternative to Radial Threshold Clustering (RTC).
- The enhanced algorithm addresses key limitations of RTC, offering improved performance and reliability.
- eQual is suitable for large-scale frame clustering tasks requiring efficiency and robust results.
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