Outlier detection using an ensemble of clustering algorithms

Autor: Shameem Ahmed, Ram Sarkar, Biswarup Ray, Soulib Ghosh, Mita Nasipuri
Rok vydání: 2021
Předmět:
Zdroj: Multimedia Tools and Applications. 81:2681-2709
ISSN: 1573-7721
1380-7501
Popis: Outlier detection is an important research area in the field of machine learning and data science. The presence of outliers in a dataset limits its true usefulness in a real-life scenario. Due to the varied challenges, researchers strive to find a general method to be useful for different datasets. In this paper, we have proposed an outlier detection technique based on unsupervised learning using an ensemble of three clustering algorithms, namely K-means, K-means++ and Fuzzy C-means. We have proposed a unique way to deal with clustered outliers. Outcomes of the three aforementioned clustering algorithms are combined intelligently to accumulate all the complementary information. To combine the decisions of the hard and soft clustering algorithms, we have proposed a novel probability-based technique, which assigns a membership value to each data point in the case of a hard clustering algorithm. Three cluster validity indices are used as our evaluation metrics, which measure the goodness of a cluster. Significant improvement of cluster validity indices is observed after removing the outliers, which ensures the removal of outliers has resulted in stringent clusters. The method is evaluated on eight datasets, among which, three datasets are comparatively large. Source code of this work is available at: https://github.com/biswarup9/Outlier-Detection-Using-an-Ensemble-of-Clustering-Algorithms- .
Databáze: OpenAIRE